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Old September 8th, 2020, 05:48 PM   #1
Onekallo
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Temperature sensitive idle?

Hey all

I have an 05 and 06 and both bikes are giving me trouble.
All carbs cleaned, valves adjusted, idle mixture screws adjusted after warmed up. Fresh oil change and newer spark plugs for both bikes.

My wife and I can fire up both bikes and they idle damn near perfectly at 1500rpm.

By the time we get to the highway (3-4 miles and a couple of stop signs) both bikes almost simultaneously are dying without some throttle. A quick idle adjustment by each of us (thankfully itís easy to reach) and itís fine. As the bikes get warmer it needs to be raised more.

Once they are parked and cooled down, a restart requires a re-adjustment of the idle or they will be reving at over 5000rpm at idle.

Any help would be great. Do we need to adjust throttle free play maybe?
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Old September 9th, 2020, 06:06 AM   #2
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Originally Posted by Onekallo View Post
Hey all

I have an 05 and 06 and both bikes are giving me trouble.
All carbs cleaned, valves adjusted, idle mixture screws adjusted after warmed up. Fresh oil change and newer spark plugs for both bikes.

My wife and I can fire up both bikes and they idle damn near perfectly at 1500rpm.

By the time we get to the highway (3-4 miles and a couple of stop signs) both bikes almost simultaneously are dying without some throttle. A quick idle adjustment by each of us (thankfully it’s easy to reach) and it’s fine. As the bikes get warmer it needs to be raised more.

Once they are parked and cooled down, a restart requires a re-adjustment of the idle or they will be reving at over 5000rpm at idle.

Any help would be great. Do we need to adjust throttle free play maybe?
Both do the exact same thing?

What is the air temp? How old is the gas?

If they idle at 1500 when cold without choke there is a problem. I would re-check the idle mixture settings. Do you know how many turns-out they are now? Have you synced the carbs lately?

Sounds like they are overall running way too rich or the gas is old/bad.

Have you cleaned and oiled the air filters lately? Too much oil can choke the airflow and make it run way rich.

Have the carbs been worked on lately?
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Old September 9th, 2020, 02:59 PM   #3
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Yes both will idle cold without choke yes. As much as they are acting the same, they are adjusted to both the same specs as well.

It is steady 15-25 deg C here (70*F)

From my calculations they are 2-2.5 turns out at the moment. That was where I intended to set them after being warmed up and idling using the 90* adjustment screw driver.

They have not been synced lately, but were completely soaked, cleaned, and rebuilt 3 times over (to make sure they will perfectly clean) roughly 250 miles ago.

Fuel is fresh.

Air filters haven’t been cleaned or oiled lately, I will do that tomorrow.

I did suspect that they were running rich. Plugs are a little black vs tan.

After an idle mixture adjustment and air filter cleaning, is there another way to lean these out? Spacer under the needle? Obviously re jetting is an option but I can’t see how that should be required if exhaust and intake is stock.

Thanks so much for the help.
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Old September 9th, 2020, 05:03 PM   #4
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Originally Posted by Onekallo View Post
Yes both will idle cold without choke yes. As much as they are acting the same, they are adjusted to both the same specs as well.

It is steady 15-25 deg C here (70*F)

From my calculations they are 2-2.5 turns out at the moment. That was where I intended to set them after being warmed up and idling using the 90* adjustment screw driver.

They have not been synced lately, but were completely soaked, cleaned, and rebuilt 3 times over (to make sure they will perfectly clean) roughly 250 miles ago.

Fuel is fresh.

Air filters havenít been cleaned or oiled lately, I will do that tomorrow.

I did suspect that they were running rich. Plugs are a little black vs tan.

After an idle mixture adjustment and air filter cleaning, is there another way to lean these out? Spacer under the needle? Obviously re jetting is an option but I canít see how that should be required if exhaust and intake is stock.

Thanks so much for the help.
That would suggest there is a carb issue. Most need a fair amount of choke (enrichener) to start, and some to keep running when cold.

Remove the air filter and go for a quick spin. It should run better if it is significantly rich. Spacers/washers under the needles will make the mixture richer.

I'm thinking something in the carbs are not right. Either the Jet Needle is not in place or the enrichener is not closing. But it's odd that they both do the same thing at the same time.

Oil the air filters sparingly. I prefer a spray air filter oil (1 light/medium coat only) instead of saturating and squeezing.

Stock Main Jet tends to be rich, but not that rich. Pilot jets are fine, and idle mixtre screws are usually in the 2 to 2.5 turns out range. The midrange (Needle Jet and Jet Needle) tend to be on the lean side, and adding a washer or 2 usually helps - but I wouldn't do that until it's running normally.
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Old September 9th, 2020, 05:44 PM   #5
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They do run so similar. It’s honestly hard to say which one might be better.

When I start them with choke, the idle is even higher.

Off idle both bikes run great and have the same amount of smooth power. Now that you are suggesting a rich condition, I guess they would be a bit “stinky” for the rider who is second in line. I had originally just chocked that up to riding behind a 15 year old carbureted twin.

I pulled the air filter from the 06 and washed it tonight. I rechecked the idle mixture screws by lightly bottoming them out, and then backing them off 2.5 turns. Tomorrow I’ll go for a ride without the filter and see if there is any improvement. If so that does prove the suspicion of a rich condition; if so what would be the next course or action? Disassemble and inspection?

I think I’m going to work on one at a time, if there is improvement on the first one at least I’ll have a baseline to work with.

Thank you so so much for your help. I really appreciate it.
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Old September 9th, 2020, 08:27 PM   #6
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What is your gas mileage? If it's significantly rich I'd expect poor fuel economy.

When riding behind my 250 I don't smell anything at all.
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Old September 9th, 2020, 09:11 PM   #7
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During carb-cleaning, did you make note of pilot jet sizes? Are they stock?

Without disassembly, perhaps experiment with leaning out mixture. Reduce mixture-screws by 1/2 turn and do test rides starting with cold engines. Any change in warmed up behavior?

Repeat again with 1/2 less on mixture screws. Repeat to point where you must use choke to start bike. How is warmed-up behavior then?

There was recent bike that would start with no choke and mixture screws turned all way in!! Turned out previous owner had drilled out jets!

Last futzed with by DannoXYZ; September 10th, 2020 at 07:52 AM.
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Old September 10th, 2020, 03:07 AM   #8
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What is your gas mileage? If it's significantly rich I'd expect poor fuel economy.

When riding behind my 250 I don't smell anything at all.
Fuel mileage is poor, and also not always the same. The best we have gotten from a tank so far is 200km (120mi) and one time it was even less.

Two nights ago we went for a ride that had a lot more high speed riding (less stop and go). Based on the mileage we had gone, we pulled in for fuel to top off close to home expecting to be almost near empty/reserve. We could only fit 1 gal in the tank.

Would it be possible that is it only super rich on the low end/idle and lean/stoich at mid to high rpm?

Last futzed with by Onekallo; September 10th, 2020 at 03:17 AM. Reason: New information
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Old September 10th, 2020, 03:10 AM   #9
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Z

During carb-cleaning, did you make note of pilot jet sizes? Are they stock?

Without disassembly, perhaps experiment with leaning out mixture. Reduce mixture-screws by 1/2 turn and do test rides starting with cold engines. Any change in warmed up behavior?

Repeat again with 1/2 less on mixture screws. Repeat to point where you must use choke to start bike. How is warmed-up behavior then?

There was recent bike that would start with no choke and mixture screws turned all way in!! Turned out previous owner had drilled out jets!

No sadly I did not make a note of the jet sizes. Thatís a great idea. Iíll give that a shot today for sure.



Based on both of your replies and information so far these bikes are definitely super rich and using way too much fuel. Thanks again so much for the help so far. Looking forward to making some progress.
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Old September 10th, 2020, 07:03 AM   #10
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So I have the 05 here with my at the shop/work.

It’s been sitting for about an 2 hours and cooled off. I put the mixture screws at 1.5 turns out and it was almost instantly better. Needed some choke to start, would idle lower if choke turned off. Going for a test ride at lunch and will re adjust again before the ride home if needed
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Old September 10th, 2020, 07:54 AM   #11
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As reference point, my commute to SF is roughly 35-miles. I get 230-260 miles between fill-ups on tank from my ‘02.

I start on full choke, then turn it off completely when I’m on hwy about 3-blocks away.
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Old September 10th, 2020, 09:22 AM   #12
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As reference point, my commute to SF is roughly 35-miles. I get 230-260 miles between fill-ups on tank from my Ď02.

I start on full choke, then turn it off completely when Iím on hwy about 3-blocks away.
Right so thatís almost double what I am getting if the best I have ever seen is 200 km.

With the small adjustment I made earlier it did make it better, but still did not require choke to start. I have the mixture screws 1/4 turn out from seated right now. Going to let it cool and try again around 2 oíclock.

Is it fair to say that if it is completely cool, and at 1/4 turn out (or less) and it still doesnít require choke to start; then there is clearly an issue beyond what can be accommodated by the mixture screws (ie needle wrong position - idle jet damaged/too big)?
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Old September 10th, 2020, 10:53 AM   #13
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Yes, getting 1/2 of typical mileage is sure sign you're dumping too much petrol into engine. If you're already at less than stock adjustment on mixture-screws and it still appears to be too rich, it would indicate something beyond external adjustments.

So most likely there's something non-stock inside carbs themselves. Non-stock jet sizes, perhaps even non-stock needles and/or heights. This is most likely issue since most common issues are in opposite direction with clogged jets & circuits causing lean mixtures.

Don't assume printed number on jets is actually what's being used. You'll want to measure jet-sizes by inserting soft-copper wire of increasing size until you find one that's snug. Then measure wire with micrometer/calipers.
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Old September 10th, 2020, 11:02 AM   #14
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Yes, getting 1/2 of typical mileage is sure sign you're dumping too much petrol into engine. If you're already at less than stock adjustment on mixture-screws and it still appears to be too rich, it would indicate something beyond external adjustments.

So most likely there's something non-stock inside carbs themselves. Non-stock jet sizes, perhaps even non-stock needles and/or heights. This is most likely issue since most common issues are in opposite direction with clogged jets & circuits causing lean mixtures.

Don't assume printed number on jets is actually what's being used. You'll want to measure jet-sizes by inserting soft-copper wire of increasing size until you find one that's snug. Then measure wire with micrometer/calipers.
Ok will do. If I can get it close with the mixture screws we will at least be able to ride for a bit longer. Once it gets a little more chilly I will tear them down again for a full inspection.

Would a "stock jet kit" be the way to go if they are indeed oversized?


Again, I cannot stress enough how thankful I am to you all for all of your patience, understanding, and support.
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Old September 10th, 2020, 12:08 PM   #15
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For a reference, I get around 27km to a litre on my ZZR riding outside of the city (80km zones) And around 25km to a litre in the city (50-60km zones). I refill every 300-320km and I am not close to the reserve. I usually put around 11-12 lites to the top at that milage. My tank might be different from 250r though.
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Old September 10th, 2020, 03:17 PM   #16
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For a reference, I get around 27km to a litre on my ZZR riding outside of the city (80km zones) And around 25km to a litre in the city (50-60km zones). I refill every 300-320km and I am not close to the reserve. I usually put around 11-12 lites to the top at that milage. My tank might be different from 250r though.
Ok thatís great. Ours are the ZZRís as well
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Old September 10th, 2020, 03:21 PM   #17
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So we just got back from a little ride.

Both bikes turned 1/4-1:8 off of seated. They will still start without the choke but would idle really low. No choke I adjusted the idle to 2000 and off we went. After a km or two the rpms dropped below 1000 and needed some throttle to stay running.

I adjusted my idle back up more to 2000, and by the next stop sign it was revving high 4-5k again. Adjusted back down and again, would die out if you didn’t give it a touch of throttle.

After a few more miles same thing. Idle adjustment almost MORE sensitive than before.

Decided to turn around and head home. Will try a new setting in the morning before heading to work on the 05
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Old September 10th, 2020, 05:22 PM   #18
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Ok that’s great. Ours are the ZZR’s as well
Did you check the jet needle to see if anyone has placed shims under ? I was experimenting with shims and put them in in winter then when started riding I started noticing rich running symptoms after about 100km and my milage was poor: 18-20km to a litre. I removed them and it started running much better and the milage improved.

Apparently shimming is a very popular mod on 250r and many people do it and see improvements. Our zzrs are jetted differently and it looks like shimming make the engine running much worse.
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Old September 10th, 2020, 05:52 PM   #19
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Also, before troubleshooting more complex carb issues did you service the enricher/choke “management system” aka cable and lever? May be they are sticky. Mine were in a poor state. I completely disassembled the lever housing cleaned it up and lubed the area where the lever slides with a bit of silicon grease. Sprayed cable lube into the cable housing using the cable lubrication contraption which cleaned the staff out and lubricated it. I have also removed and lubricated the enricher slide. Then checked the cable tention and slack. Our ZZRs I believe have the cable length adjustment built intk the canle housing. I think its located under the tank. Just make sure your cable opens and closes the enricher valves properly. After I did mine it works way better, I can adjust almost in 1000 rpm increments when its cold.
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Old September 10th, 2020, 09:54 PM   #20
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Originally Posted by Onekallo View Post
So we just got back from a little ride.

Both bikes turned 1/4-1:8 off of seated. They will still start without the choke but would idle really low. No choke I adjusted the idle to 2000 and off we went. After a km or two the rpms dropped below 1000 and needed some throttle to stay running.

I adjusted my idle back up more to 2000, and by the next stop sign it was revving high 4-5k again. Adjusted back down and again, would die out if you didn’t give it a touch of throttle.

After a few more miles same thing. Idle adjustment almost MORE sensitive than before.

Decided to turn around and head home. Will try a new setting in the morning before heading to work on the 05
Ok, this is close to stock behavior. Don't adjust idle-speed, use choke instead when it's cold start. That's why there's choke-lever on left handlebar. Then by next stop-sign when it's starting to rev up, lower choke gently to set revs around 2000rpms. By time it's fully warmed-up, you should be able to turn off choke completely. This is when you should have idle-speed set to 1500rpm and leave it there for good. Don't touch idle adjuster ever again, just use choke for cold starts.

Choke-cable on my EX250J isn't adjustable. There's about 3-5mm of initial lever-pull that doesn't move choke-lever on carbs. Maximum lever-pull is determined by max choke throw on carb. Reducing choke has carb reach stop just before lever hits end of travel. Might want to visually check your choke movement at carb to verify its movement matches lever without excessive play on either end.

Having mixture-screws close to fully closed for normal start behavior would definitely indicate too-large of pilot jets. However if it behaves like stock with them screwed in, that might balance things.

Next would be seeing how gas-mileage changes. Cruising is combination of pilot and needles/main-jets. So there should be improvement right away.

My '08 EX250J new-gen has 17-ltr tank. ZZR250 and EX250F pre-gens have 18-ltr tank. So I'm getting about 25-28 km/ltr with 15-ltr fill-ups..
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Old September 11th, 2020, 03:16 AM   #21
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Ok, this is close to stock behavior. Don't adjust idle-speed, use choke instead when it's cold start. That's why there's choke-lever on left handlebar. Then by next stop-sign when it's starting to rev up, lower choke gently to set revs around 2000rpms. By time it's fully warmed-up, you should be able to turn off choke completely. This is when you should have idle-speed set to 1500rpm and leave it there for good. Don't touch idle adjuster ever again, just use choke for cold starts.
Stupid question but now how do I get the idle back?

Can’t remember where it was set. Let’s say I give it full choke this morning and it fires up but revs at 5k; is that normal? Then I would leave idle setting as is and as it warms up remove choke?

Sorry I am excited you believe it is almost close, but want to make sure I can get it back there.

Thanks so much.



Side bar, choke is smooth and does come on and off. Cables move freely and so does actual valve from a quick inspection last night.
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Old September 11th, 2020, 04:19 AM   #22
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Stupid question but now how do I get the idle back?

Canít remember where it was set. Letís say I give it full choke this morning and it fires up but revs at 5k; is that normal? Then I would leave idle setting as is and as it warms up remove choke?

Sorry I am excited you believe it is almost close, but want to make sure I can get it back there.

Thanks so much.



Side bar, choke is smooth and does come on and off. Cables move freely and so does actual valve from a quick inspection last night.
The way my bike starts: Choke to full open, she fires up runs at low(1k rpms) , but in a couple of seconds the tach goes to about 5-6k, I lower it to about 3k and start riding. The rev would stay at 3k on the stops when I roll of the throttle. I ride like that for 1-2kms and then close the choke. The revs would go down to the preset value. At the time when the coolant temp gauge shows at least 1/3rd I double check the revs when the throttle is off and adjust if necessary. Mine is set at about 1.3-1.4k
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Old September 11th, 2020, 04:51 AM   #23
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The way my bike starts: Choke to full open, she fires up runs at low(1k rpms) , but in a couple of seconds the tach goes to about 5-6k, I lower it to about 3k and start riding. The rev would stay at 3k on the stops when I roll of the throttle. I ride like that for 1-2kms and then close the choke. The revs would go down to the preset value. At the time when the coolant temp gauge shows at least 1/3rd I double check the revs when the throttle is off and adjust if necessary. Mine is set at about 1.3-1.4k
Ok so I just left home.

Started full choke, got it to rev at 5k full choke, went to about half-3/4 and then it idle nicely at 3k +/-.

Rode fine no problem. My commute is quite short (5 km and its only 10*C this morning) so the temp gauge did not move at all. Just for S's and G's I backed off the choke as I pulled in the driveway, and the bike almost died right out.

Hoping to go for a bit longer ride at lunch with the same starting procedure in order to warm it up a bit more. This is going to be such a stupid question (sorry my head it so twisted trying to figure this all out) but does it make sense for the revs to drop as the bike warms up and the choke is removed? If I am increasing the idle with more choke, as it warms up should the bike not idle higher, and then less choke would even it out again?


Thank you all so much again I truly appreciate all of the help and guidance, I honestly do.
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Old September 11th, 2020, 07:09 AM   #24
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Ok so I just left home.

Started full choke, got it to rev at 5k full choke, went to about half-3/4 and then it idle nicely at 3k +/-.

Rode fine no problem. My commute is quite short (5 km and its only 10*C this morning) so the temp gauge did not move at all. Just for S's and G's I backed off the choke as I pulled in the driveway, and the bike almost died right out.

Hoping to go for a bit longer ride at lunch with the same starting procedure in order to warm it up a bit more. This is going to be such a stupid question (sorry my head it so twisted trying to figure this all out) but does it make sense for the revs to drop as the bike warms up and the choke is removed? If I am increasing the idle with more choke, as it warms up should the bike not idle higher, and then less choke would even it out again?


Thank you all so much again I truly appreciate all of the help and guidance, I honestly do.
No question is stupid I see the rpms go up about 20% with the choke still in place and the engine warming up. But I do not monitor it really I just close the choke after 1-2km. You can try to ride for a couple of kms on your lunch then set the idle with the choke closed. Then see how the bike behaves on the way home. Here is the description on how to use the choke https://faq.ninja250.org/wiki/What_i..._at_startup%3F
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Old September 14th, 2020, 04:30 AM   #25
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Originally Posted by SibSerge View Post
No question is stupid I see the rpms go up about 20% with the choke still in place and the engine warming up. But I do not monitor it really I just close the choke after 1-2km. You can try to ride for a couple of kms on your lunch then set the idle with the choke closed. Then see how the bike behaves on the way home. Here is the description on how to use the choke https://faq.ninja250.org/wiki/What_i..._at_startup%3F
Well I ended up putting both bikes back to 2.5 turns out. There is little left in the riding season based on our schedules, and as much as they ran rich, at least they ran smooth and not all over the place.

In a few weeks or so I will be tearing them back apart again and inspecting the Jets, needles, enrichener movement etc. With the idle mixture screws completely closed it still ran rich and not as you are all describing it should.

I appreciate all of your help thus far, and will continue to update the thread as I progress.

Thank you again.
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Old September 14th, 2020, 06:02 AM   #26
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Originally Posted by Onekallo View Post
Well I ended up putting both bikes back to 2.5 turns out. There is little left in the riding season based on our schedules, and as much as they ran rich, at least they ran smooth and not all over the place.

In a few weeks or so I will be tearing them back apart again and inspecting the Jets, needles, enrichener movement etc. With the idle mixture screws completely closed it still ran rich and not as you are all describing it should.

I appreciate all of your help thus far, and will continue to update the thread as I progress.

Thank you again.
Something definitely isn't right inside the carbs then.
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Old September 14th, 2020, 06:30 AM   #27
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Something definitely isn't right inside the carbs then.
Clearly. I will order some new stock jets for both bikes so that one they are torn down I can at least have them to compare, and likely replace. It sounds as though the main isn't an issue, but for the cost of what they are; I will likely replace them at the same time.
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Old September 14th, 2020, 09:34 AM   #28
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"With the idle mixture screws completely closed it still ran rich and not as you are all describing it should".

With idle screws closed it should not run at all. Along with some of your other symptoms ...a clear indication of unmetered fuel bypassing normal circuits and entering the venturi.
If jets are not monster oversized, I'd be willing to submit a float valve control issue exists. Fuel levels are begging to be checked via "clear tube" method.
(they can be out of spec and still not visibly leak all over the floor, for example )

Didn't I read on the internet "carbs are easy"? Right, sure they are. Precision little boogers....lotta various stuff goin' on inside there.
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Old September 14th, 2020, 12:12 PM   #29
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Originally Posted by Onekallo View Post
Clearly. I will order some new stock jets for both bikes so that one they are torn down I can at least have them to compare, and likely replace. It sounds as though the main isn't an issue, but for the cost of what they are; I will likely replace them at the same time.
Please keep in mind that ZZR250 jet sizes are different than regular 250. I do not remember the numbers now but I should have a manual addend. at home I will try to find them. I would not order spare jets unless you order OEM. Better clean yours if you still have OEM in your carbs. And I did check it - the orignal jets are expensive, I would not do that unless what you have is aftermarket or damaged.
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Old September 14th, 2020, 02:09 PM   #30
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Here is the spec, just in case.
Attached Images
File Type: png Screen Shot 2020-09-14 at 5.07.56 PM.png (525.6 KB, 10 views)
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Old September 14th, 2020, 09:29 PM   #31
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Originally Posted by Onekallo View Post
Well I ended up putting both bikes back to 2.5 turns out. There is little left in the riding season based on our schedules, and as much as they ran rich, at least they ran smooth and not all over the place.
Looks like stock setting is 1.5-turns out on mixture screws.

All over the place because you keep on adjusting idle-screw. Leave that alone and learn to use choke lever.

1. Cold start - 3/4 to full choke to start. If idle too slow, increase choke. If idle too fast, decrease choke. No change in idle-speed adjuster necessary.

2. Once started, adjust choke-lever for 3-4k RPM. If idle too fast, decrease choke. If idle too slow, increase choke. No adjustments to idle-speed necessary. Start your ride

3. In 5-10 min, if you stop, reduce choke again to lower idle-speed to 2-3k RPMs. If idle too high, decrease choke. If idle too slow, increase choke. No adjustment necessary on idle-speed screw.

4. 10-15 min, turn choke completely off after bike’s warmed up.

That’s it! Never ever need to adjust idle-speed knob. It’s all done conveniently and quickly with choke lever.

Last futzed with by DannoXYZ; September 16th, 2020 at 05:22 PM.
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Old September 15th, 2020, 04:56 AM   #32
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Originally Posted by ducatiman View Post
With idle screws closed it should not run at all. Along with some of your other symptoms ...a clear indication of unmetered fuel bypassing normal circuits and entering the venturi.
If jets are not monster oversized, I'd be willing to submit a float valve control issue exists. Fuel levels are begging to be checked via "clear tube" method.
(they can be out of spec and still not visibly leak all over the floor, for example )
.
10-4. Will verify fuel level and and float control upon disassembly. Thank you
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Old September 15th, 2020, 04:58 AM   #33
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Originally Posted by SibSerge View Post
Please keep in mind that ZZR250 jet sizes are different than regular 250. I do not remember the numbers now but I should have a manual addend. at home I will try to find them. I would not order spare jets unless you order OEM. Better clean yours if you still have OEM in your carbs. And I did check it - the orignal jets are expensive, I would not do that unless what you have is aftermarket or damaged.
My plan was to order OEM from our local dealer based off of the bikes VIN. I will inspect sizing first as you suggest.

Thank you
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Old September 15th, 2020, 05:04 AM   #34
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Originally Posted by DannoXYZ View Post
Looks like stock setting is 1.5-turns out on mixture screws.

All over the place because you keep on adjusting idle-screws. Leave those alone and learn to use choke lever.

1. Cold start - 3/4 to full choke to start. If idle too slow, increase choke. If idle too fast, decrease choke. No change in idle-speed adjuster necessary.

2. Once started, adjust choke-lever for 3-4k RPM. If idle too fast, decrease choke. If idle too slow, increase choke. No adjustments to idle-speed necessary. Start your ride

3. In 5-10 min, if you stop, reduce choke again to lower idle-speed to 2-3k RPMs. If idle too high, decrease choke. If idle too slow, increase choke. No adjustment necessary on idle-speed screw.

4. 10-15 min, of turn choke full off after bike’s warmed up.

That’s it! Never ever need to adjust idle-speed knob. It’s all done conveniently and quickly with choke lever.
Thanks DannoXYZ.

I will try this method on the way home.

Since I have been adjusting the idle-speed knob excessively, I am not sure where it currently is.

Is there a base setting for that, or is it completely irrelevant?

Example; is the factory setting a certain number of turns off bottomed out, or does your method apply no matter the current position of the idle-speed knob

Please don't take this as me not trusting or believeing in your method, I just want to make sure I am following it as closely as possible to achieve the proper results.




Thank you again to everyone for all of the assistance. Once again, truly appreciated.
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Old September 15th, 2020, 05:55 AM   #35
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Originally Posted by Onekallo View Post
Thanks DannoXYZ.

I will try this method on the way home.

Since I have been adjusting the idle-speed knob excessively, I am not sure where it currently is.

Is there a base setting for that, or is it completely irrelevant?

Example; is the factory setting a certain number of turns off bottomed out, or does your method apply no matter the current position of the idle-speed knob

Please don't take this as me not trusting or believeing in your method, I just want to make sure I am following it as closely as possible to achieve the proper results.




Thank you again to everyone for all of the assistance. Once again, truly appreciated.
Just run the bike at any rpm for few mins before taking for a ride. Close the choke and set your idle around 1.4k rpm with the choke closed. That would be a sufficient baseline. Then adjust it when you come to your destination to the spec.
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Old September 15th, 2020, 06:07 AM   #36
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Originally Posted by Onekallo View Post
Thanks DannoXYZ.

I will try this method on the way home.

Since I have been adjusting the idle-speed knob excessively, I am not sure where it currently is.

Is there a base setting for that, or is it completely irrelevant?

Example; is the factory setting a certain number of turns off bottomed out, or does your method apply no matter the current position of the idle-speed knob

Please don't take this as me not trusting or believeing in your method, I just want to make sure I am following it as closely as possible to achieve the proper results.




Thank you again to everyone for all of the assistance. Once again, truly appreciated.
Just run the bike at any rpm for few mins before taking for a ride. Close the choke and set your idle around 1.4k rpm with the choke closed. That would be a sufficient baseline. Then adjust it when you come to your destination to the spec.
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Old September 15th, 2020, 06:36 AM   #37
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If you are trying to make it ride-able now, I would start by getting the idle mixture screws set as good as possible.

To do that, warm the engine fully and let it idle. Adjust the screws one at a time to get the highest idle speed. Then adjust the idle speed to 1300 +/-. I typically go about 1/8-turn richer after reaching highest speed, which helps smooth the transition off-idle. For now, just get the highest speed.

That's assuming the carbs are synced properly. If they were way off you may not be able to get a proper idle.
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Old September 16th, 2020, 05:02 PM   #38
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Quote:
Originally Posted by Onekallo View Post
Since I have been adjusting the idle-speed knob excessively, I am not sure where it currently is.

Is there a base setting for that, or is it completely irrelevant?

Example; is the factory setting a certain number of turns off bottomed out, or does your method apply no matter the current position of the idle-speed knob
No base-setting for idle. Just whatever position is needed for proper idle-speed of 1300 +/- 100rpms. Follow JKV's procedure:

Quote:
1. To do that, warm the engine fully and let it idle.
2. Adjust the [mixture] screws one at a time to get the highest idle speed. I typically go about 1/8-turn richer after reaching highest speed, which helps smooth the transition off-idle. For now, just get the highest speed.
3. Then adjust the idle speed to 1300 +/-.
So order is:

- mixture-screws for highest idle-speed + 1/8 turn
- idle-speed set to 1300rpms
- leave both those alone permanently and use choke for cold-starts. Its range is greater than all others.
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Old September 17th, 2020, 05:10 AM   #39
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No base-setting for idle. Just whatever position is needed for proper idle-speed of 1300 +/- 100rpms. Follow JKV's procedure:



So order is:

- mixture-screws for highest idle-speed + 1/8 turn
- idle-speed set to 1300rpms
- leave both those alone permanently and use choke for cold-starts. Its range is greater than all others.
So;

I verify Pilot and Main jet sizing (replace as needed)

Set the fuel / float level using the clear tube method on the bench. (currently set to 17mm, but now after reading/watching the clear tube method I understand the importance of the clear tube method, and that the spec is +/- 2mm)

Start the bike and warm it up by riding for 10-15 minutes.

Adjust mixture screws so that they are at the highest idle (no throttle input) speed achievable (even if that is 5-6k?)

Turn mixture screws 1/8 turn more rich.

Adjust idle to 1300 rpm

Shut off bike, start in the morning using choke and only choke and pretend the idle adjustment is dead to me and never look at it again.

Correct?


I once again sincere;y apologies for all of the questions, but also am so thankful for all of your patience and support. I cannot express that enough
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Old September 17th, 2020, 05:35 AM   #40
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So;

Adjust mixture screws so that they are at the highest idle (no throttle input) speed achievable (even if that is 5-6k?)
No, at that speed the carbs are beyond the idle circuits. Don't let the engine get above 1,500-1,800 rpm for this adjustment.

Quote:
Shut off bike, start in the morning using choke and only choke and pretend the idle adjustment is dead to me and never look at it again.
That's a bit extreme. Although I don't adjust my idle speed very often, they did put that knob there to make it easy to do, and I occasionally make a small change, depending on air temperature and other influences.

That's not really a choke, you know. It's an enricher that adds air and gasoline, which is why the engine speeds up at the same time the mixture gets richer.
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