Slip on exhaust runs hot?

mista350z · August 5th, 2009, 09:55 PM

Ok so I installed the 2bros slip on exhaust last week. I rode a couple times for about 45min/per ride. My bike ran extremely hotter than usual. The gas tank was super hot. The weather was like any normal day and this just started happening when i installed the exhaust. Another thing I noticed was that my idle went from 1500 to about 1800-2200 at times. I didnt do any other modifications to the bike yet. Is this normal? I am kind of scared of over heating my bike.

kkim · August 5th, 2009, 10:43 PM

you are running lean. lean conditions produce more heat. how lean is too lean? dunno, but if I were you, I'd at least shim the needles if not do a rejet.

...but gee, doesn't that exhaust sound good?

mista350z · August 6th, 2009, 12:24 AM

Exhaust sounds mean. Kinda loud at night. Afraid to wake the neighbors....So will anything happen to the engine if I dont shim or rejet? I plan to eventually, just to lazy to actually sit down and rip apart the bike.

kkim · August 6th, 2009, 01:15 AM

most likely not, but it can burn valves if too lean. best way to tell is to do a plug color check, but if you're too lazy to rejet I suspect you won't be interested in a plug check either.

good luck

Cali619 · August 6th, 2009, 02:12 PM

if you dont want to shim the needles yourself Im sure a local shop can hook it up for cheap

a10forwar · August 13th, 2009, 05:50 PM

I shimmed my needles two days ago and it was alot more difficult than I thought it would be. SO BE CAREFULL. Here is a list of things you need to pay attention too.

1. When removing the gas tank be carefull for the electrical connector, mine had barely enough slack to disconnect.

2. When removing the plastic caps on the carb, use alot of pressure on the screws. They are hard to get to and you may end up striping one out. And that would be bad.

3.Rt side is easier to do, by far. 4 black screws with nothing in your way sorta. I started with this one first for confidence of completion.

4. Lt side has 3 silver screws and 1 black screw. 1 silver screw for the choke cable bracket and 2 silver screws for a vacuum valve of some sort. The choke cable bracket is easy to move out of the way. Just move it forward. The vaccuum valve on the left has two hoses that go between the rt and lt carbs. I moved the vacuum valve with bracket lt and aft to get the best clearance. The hoses then split the carbs for easy removal of cap.

5. Be very carefull with each vacuum due to the fact that these are made to be a very thin membrane. Make sure when putting them back on you take your finger and ever so slightly rub the circumfrence of the vacuum to position the seal into the groove.

6. Take your time, mark everything and have fun. This is not intended to be a full HOW-TO. Just key details I thought might be important.

kkim · August 13th, 2009, 07:38 PM

Yep, James... all valid points.

So, how does the bike feel after shimming? have you pull off the snorkel yet?

Sound Wave · August 15th, 2009, 01:16 AM

Quote:

Originally Posted by a10forwar

5. Be very carefull with each vacuum due to the fact that these are made to be a very thin membrane. Make sure when putting them back on you take your finger and ever so slightly rub the circumfrence of the vacuum to position the seal into the groove.

if you use a pair of tweezers and grab out the needles, then you don't have to remove the diaphragms. still would be a good idea to double check their position before putting the caps back on though.

a10forwar · August 15th, 2009, 11:15 AM

Never thought about tweezers good idea. But I looked down there to see the needle before I pulled it though.

Funny thing it backfired as soon as I started it. It does start better though will probably never usr choke, never did before though either. Havent been in cold season yet. Oh well. Rides good. Little better control and gears seem longer. Mostly 3rd ?? I hope I didnt put too much shim on it. Two washers .032 total. No mods on eng yet. No exhaust mod either.

August 5th, 2009, 09:55 PM	#1
mista350z ninjette.org member Name: John Location: The OC Join Date: Feb 2009 Motorcycle(s): 08 CBR600rr, 08 Ninja 250r - sold Posts: 81	Slip on exhaust runs hot? Ok so I installed the 2bros slip on exhaust last week. I rode a couple times for about 45min/per ride. My bike ran extremely hotter than usual. The gas tank was super hot. The weather was like any normal day and this just started happening when i installed the exhaust. Another thing I noticed was that my idle went from 1500 to about 1800-2200 at times. I didnt do any other modifications to the bike yet. Is this normal? I am kind of scared of over heating my bike.

August 6th, 2009, 02:12 PM	#5
Cali619 Giggity Giggity Name: Ryam Location: San Diego Join Date: Feb 2009 Motorcycle(s): 08 ninja 250R aka Hiryu Posts: 481	if you dont want to shim the needles yourself Im sure a local shop can hook it up for cheap __________________________________________________ Facebook DY Fender chop, Danmoto CB slip-on w/baffle, Airbox removed, Kleen-air removed, shimmed needles, Mikuni #117.5 Main jets, K&N RU-1822 air filter pods

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August 5th, 2009, 10:43 PM	#2
kkim Join Date: Nov 2008 Posts: Too much.	you are running lean. lean conditions produce more heat. how lean is too lean? dunno, but if I were you, I'd at least shim the needles if not do a rejet. ...but gee, doesn't that exhaust sound good?

August 6th, 2009, 12:24 AM	#3
mista350z ninjette.org member Name: John Location: The OC Join Date: Feb 2009 Motorcycle(s): 08 CBR600rr, 08 Ninja 250r - sold Posts: 81	Exhaust sounds mean. Kinda loud at night. Afraid to wake the neighbors....So will anything happen to the engine if I dont shim or rejet? I plan to eventually, just to lazy to actually sit down and rip apart the bike.

August 6th, 2009, 01:15 AM	#4
kkim Join Date: Nov 2008 Posts: Too much.	most likely not, but it can burn valves if too lean. best way to tell is to do a plug color check, but if you're too lazy to rejet I suspect you won't be interested in a plug check either. good luck

August 13th, 2009, 05:50 PM	#6
a10forwar ninjette.org member Name: James Location: GE Join Date: Aug 2009 Motorcycle(s): 09 Ninja 250R SE Posts: 31	I shimmed my needles two days ago and it was alot more difficult than I thought it would be. SO BE CAREFULL. Here is a list of things you need to pay attention too. 1. When removing the gas tank be carefull for the electrical connector, mine had barely enough slack to disconnect. 2. When removing the plastic caps on the carb, use alot of pressure on the screws. They are hard to get to and you may end up striping one out. And that would be bad. 3.Rt side is easier to do, by far. 4 black screws with nothing in your way sorta. I started with this one first for confidence of completion. 4. Lt side has 3 silver screws and 1 black screw. 1 silver screw for the choke cable bracket and 2 silver screws for a vacuum valve of some sort. The choke cable bracket is easy to move out of the way. Just move it forward. The vaccuum valve on the left has two hoses that go between the rt and lt carbs. I moved the vacuum valve with bracket lt and aft to get the best clearance. The hoses then split the carbs for easy removal of cap. 5. Be very carefull with each vacuum due to the fact that these are made to be a very thin membrane. Make sure when putting them back on you take your finger and ever so slightly rub the circumfrence of the vacuum to position the seal into the groove. 6. Take your time, mark everything and have fun. This is not intended to be a full HOW-TO. Just key details I thought might be important.

August 13th, 2009, 07:38 PM	#7
kkim Join Date: Nov 2008 Posts: Too much.	Yep, James... all valid points. So, how does the bike feel after shimming? have you pull off the snorkel yet?

August 15th, 2009, 11:15 AM	#9
a10forwar ninjette.org member Name: James Location: GE Join Date: Aug 2009 Motorcycle(s): 09 Ninja 250R SE Posts: 31	Never thought about tweezers good idea. But I looked down there to see the needle before I pulled it though. Funny thing it backfired as soon as I started it. It does start better though will probably never usr choke, never did before though either. Havent been in cold season yet. Oh well. Rides good. Little better control and gears seem longer. Mostly 3rd ?? I hope I didnt put too much shim on it. Two washers .032 total. No mods on eng yet. No exhaust mod either.