Carbs and Tires (Newb Questions)

[TBC]

Hi guys! First off, the carbs:

I just got back from a relatively long trip (~2 months) and started the bike up for the first time. It took quite a bit of time to get it started (no surprise there), but also took a long time to warm it. It was about ten minutes of running with full choke before the bike wouldn't die when throttle was given. After that, removing any choke would kill the engine. Additionally, throttle input was sluggish and the needle on the tach seemed to "hang."

Thirty minutes of riding later, it was still exhibiting the same problem. After that I shut it off and parked it. The next day I rode it back to the garage, and it still showed the same problem initially. But after twenty minutes of riding I pulled over, turned off the choke, and it ran fine.

I'm guessing the issue was either a.) stale gas (I put Stabil in the tank before I left) or b.) clogged carbs? I'm still trying to learn the mechanics of everything, but that's what it seems to be.

As such, I've decided to pull the carbs anyways to just give them a once-over. A friend recommended getting a carb rebuild kit, though most of the ones online for the 250 I've found seem to be around $30 (and you would need two of them?). That seems like a waste - is a rebuild kit really needed? If so, are there any inexpensive alternatives?



Secondly: the tires. Or tire, rather. I just took a look at the rear tire after that first ride, and I noticed that there seems to be no tread in the center of the tire, in an area of about 1 and 1/2 inches wide. Does this mean I need to replace the tire? Do I still have a few miles left?

Any help is greatly appreciated!

[Alex]

Carbs: If it's now running correctly, fuel mileage is normal, and starting is normal, I wouldn't disassemble anything. If anything, just run some fuel system cleaner like seafoam through the next tank and don't worry about it.

Tires: If you're past the wear bars in the center (and no tread means you're way past them), replace 'em.

[TBC]

Originally Posted by Alex

Carbs: If it's now running correctly, fuel mileage is normal, and starting is normal, I wouldn't disassemble anything. If anything, just run some fuel system cleaner like seafoam through the next tank and don't worry about it.

Thanks for the help Alex!

Starting and running - it takes awhile to warm up, and I feel a bit of hesitation with the throttle. I also wanted to clean them just for peace-of mind. But you would say to leave them alone for now?

Originally Posted by Alex

Tires: If you're past the wear bars in the center (and no tread means you're way past them), replace 'em.

That's the vertical line running through the center of the tire?

Any suggestions on replacement tires (and how much getting it changed will run)?

[sc37]

Originally Posted by TBC

Thanks for the help Alex!

That's the vertical line running through the center of the tire?

Any suggestions on replacement tires (and how much getting it changed will run)?

Look at the sides...there will be an arrow pointing to the spots where there are wear bars.

[Alex]

Originally Posted by TBC

Starting and running - it takes awhile to warm up, and I feel a bit of hesitation with the throttle. I also wanted to clean them just for peace-of mind. But you would say to leave them alone for now?

It's up to you. Certainly wouldn't hurt anything to clean them out if you wanted to undertake it.

Originally Posted by TBC

Any suggestions on replacement tires (and how much getting it changed will run)?

Two tire wikis for the pregen:

http://faq.ninja250.org/wiki/What_ti...fit_the_250%3F

and

http://www.ninjette.org/wiki/Tire_options_-_pregens

I always preferred the Sport Demons on my pregen. YMMV.

[TBC]

Thanks to you both! I'll take a look at the tires for those "wear bars" you're talking about.

[jayman87]

Originally Posted by TBC

I'm guessing the issue was either a.) stale gas (I put Stabil in the tank before I left) or b.) clogged carbs? I'm still trying to learn the mechanics of everything, but that's what it seems to be.

When you say you put Stabil in tank, did you just pour some in and walk away, or did you put some in the run the bike long enough that it reached the carbs.

If you didn't, you should slush it around in the tank to help it fully mix with the gas. Then you have to either drain the float bowls on the carbs, or run the bike long enough to replace the gas in the float bowls with stabil+gas mix.

[TBC]

Originally Posted by jayman87

When you say you put Stabil in tank, did you just pour some in and walk away, or did you put some in the run the bike long enough that it reached the carbs.

If you didn't, you should slush it around in the tank to help it fully mix with the gas. Then you have to either drain the float bowls on the carbs, or run the bike long enough to replace the gas in the float bowls with stabil+gas mix.

IIRC I ran the bike for a bit after putting Stabil in the tank. But I'm not certain. Regardless - wouldn't running the bike for thirty minutes be plenty of time for the gas in the float bowls to be completely replaced by new gas (with the Stabil mixed in)?

Here's a rather poor photograph of the tire I just took. SC - I couldn't locate the wear bars, any advice for finding them?

[Alex]

They are completely gone. Replace the tire.

[davenay67]

This isn't a tire....it's a slick..!!

Seriously though, you are way past the safe time to replace this tire. You are much more prone to punctures when it gets this worn.

As for the carbs, do as Alex suggested and try a dose of SeaFoam thru the crbs before you remove them. If it's still not quite right then go ahead and pull the carbs for a manual cleaning.

[TBC]

Thanks again Alex and Dave. Any idea how much a shop would charge for changing the tire out?

[Alex]

Varies, call around. If you remove the wheel from the bike, and bring it in loose with a tire you want mounted/balanced, you might find a shop in the $15 - $20 range. If you ride the bike in, and say "give me a new rear tire", they might charge as much as $50 - $75 to remove, mount/balance, re-install the wheel. Plus the cost of the tire itself in both cases.

[davenay67]

Originally Posted by Alex

Varies, call around. If you remove the wheel from the bike, and bring it in loose with a tire you want mounted/balanced, you might find a shop in the $15 - $20 range. If you ride the bike in, and say "give me a new rear tire", they might charge as much as $50 - $75 to remove, mount/balance, re-install the wheel. Plus the cost of the tire itself in both cases.

Agreed. Bottom line is to call around and get the price on the tire you need and their cost to mount/balance the new tire. Be sure to remove the wheel yourself and take the rim in....much cheaper....let me them that's what you will be doing when you ask prices.

I couldn't even ballpark the cost, because I don't know your area and I been mounting/balancing my own tires for the past 5 years.

[TBC]

Originally Posted by davenay67

Agreed. Bottom line is to call around and get the price on the tire you need and their cost to mount/balance the new tire. Be sure to remove the wheel yourself and take the rim in....much cheaper....let me them that's what you will be doing when you ask prices.

I couldn't even ballpark the cost, because I don't know your area and I been mounting/balancing my own tires for the past 5 years.

I only called one shop so far, and they quoted ~$30-40 to mount/balance the tire if the old one was still on the bike. But the price for just the rear tire is going to be $150-$200 or so.

I'm not sure where else around here could service the bike, to be honest. But I'll call around.

[drdriftking007]

Originally Posted by TBC

I only called one shop so far, and they quoted ~$30-40 to mount/balance the tire if the old one was still on the bike. But the price for just the rear tire is going to be $150-$200 or so.

I'm not sure where else around here could service the bike, to be honest. But I'll call around.

Bike bandit you can buy front and rear for $130

[NJ Ninjette]

I bought my tires online and the cheapest price I could find around my way was $40 per tire off the bike. It was as much as $100 per tire on the bike.

But all of them said it would've been much cheaper if I bought the tires from them, what that didn't say was the cost of the tires would've been much more.

I bought a manual tire changer years ago for doing my dirtbike tires, but never even set it up. For the kind of money the shops around here are charging now I busted it out and am going to do them myself. I may even do some on the side and make few extra bucks.

Any bike shop can change your tires doesn't matter the brand, you may even find a mechanic shop or gas station. Doesn't hurt to ask around to any place that could possibly do it.

I once paid a buddy a 12 pack to change the rear tire on my old XR 400 because I didn't feel like doing it. He came over with his favorite two tire irons, used some of my dish detergent, and was finished in about 20 mins and three beers later. We then killed the rest, money well spent.

[TBC]

Thanks again for all of the help guys! Joe - I'm not sure I'm quite up for changing the tire myself quite yet! Eddie - should I replace the front as well?

I talked to a number of different shops today, and most quoted me around $50 for the service (with the tire on the bike). A guy at one of the shops said that he could sell me the stock tire (Dunlop K630 I believe?) and the service for $150 out the door.

But he also recommended that I not put a different tire on the rear if I had the stock tire on the front, given that two different tires act different and could potentially be more dangerous. Is there truth to that? The stock tires seem to get a lot of flak on here, so I want to avoid buying another if they really are that bad.

Somewhat related: The bike is an '04 with only ~4300 miles on it. The previous owner(s) had no service records, and so I'm not certain, but it's entirely possible that with the low mileage the bike still has its stock tires. Do I need to worry about having a front tire that is eight years old at this point? Replacing both tires is quite pricey (even with the stock tires), and I'd much rather not spend the cash unless I have to .

In other news, a friend and I are going to pull the carbs and give them a good cleaning tomorrow. I'll report back with photos when I can .

[Alex]

I'd replace both tires at once. After 5 years, they are pretty much done, and they weren't great when new. Your bike will feel like a different machine with quality tires front rear. Don't pick the K630's.

Pirelli Sport Demons
Pirelli Diablo Scooter
MT75's
GT501's

Any of them are orders of magnitude better than the the K630's.

You can confirm the age of the tires on your bike (and on any bike) by looking at the 4 digit date code on the sidewall, representing when it was manufactured. The last 2 digits are the year, and the first two digits are the week in that year. Odds are your tires say XX04 or even XX03.

[n4mwd]

Originally Posted by TBC

As such, I've decided to pull the carbs anyways to just give them a once-over. A friend recommended getting a carb rebuild kit, though most of the ones online for the 250 I've found seem to be around $30 (and you would need two of them?). That seems like a waste - is a rebuild kit really needed? If so, are there any inexpensive alternatives?

I've seen single carb rebuild kits go for about $15 each or a pair HERE for about $30.

Generally speaking, unless your carb is seriously messed up, you don't really need the kits. The only thing in there that you might need is the main gasket. However, a lot of people just reuse the old one and it works just fine. Just be careful removing it.

If you continue to have problems, I would pull the carbs and check the two jets in both carbs. In your case, since it was running before, there is probably no need to soak it in anything. There are DIY's that show how to rebuild them without damaging the diaphragms that you can look at if you aren't familiar with the process.

For future reference, if you plan on letting the bike sit for more than a week or two, you need to drain the carbs. There are two ways to do that. The hard way is to use an allen wrench and open the petcock on each bowl and let it drain out. The easy way is to turn the gas tank petcock to OFF and then ride the bike around the yard. Takes about 5 minutes. In both cases, you want to leave the main tank petcock OFF when finished.

[TBC]

A friend and I pulled the carbs this weekend, cleaned them, and put them back on the bike. It feels like it's running better, and that's always a good sign.

Originally Posted by Alex

I'd replace both tires at once. After 5 years, they are pretty much done, and they weren't great when new. Your bike will feel like a different machine with quality tires front rear. Don't pick the K630's.
...
Odds are your tires say XX04 or even XX03.

Looking at sides of the tires, I think they're '03. It looks like I'm probably going to be getting a full set of...*something* in the very near future.

[FrugalNinja250]

I generally recommend Kenda K671 touring tires as they're inexpensive, durable, and have good traction. I've gotten the rear for less than $80 shipped, though I do my own installation. My last rear one went over 25k miles. Fronts go over 27,000 miles.

[TBC]

Originally Posted by FrugalNinja250

I generally recommend Kenda K671 touring tires as they're inexpensive, durable, and have good traction. I've gotten the rear for less than $80 shipped, though I do my own installation. My last rear one went over 25k miles. Fronts go over 27,000 miles.

Is it okay to put touring tires on a sport(ish) bike?

[FrugalNinja250]

Absolutely!

[TBC]

Thanks for all of the advice - I've decided to get a set of Sport Demons for the front and rear. Just to triple check: 100/90-16 and 130/90-16, correct?

[n4mwd]

Originally Posted by TBC

Thanks for all of the advice - I've decided to get a set of Sport Demons for the front and rear. Just to triple check: 100/90-16 and 130/90-16, correct?

Yes, I believe so.

[TBC]

Okay! Placed the order - they should be in this Wednesday, on the bike before this weekend. Again - thanks for all of the help everyone!

[TBC]

Ugh. Updating before new tires - just went down to check on everything before heading to the shop, and the bike is leaking *something*. It's been sitting down there for two weeks undisturbed, so whatever was on the ground is either fresh or relatively persistent. Liquid is somewhat thick and a reddish/rose color. To my untrained eye I think it's oil.

I found an unattached hose leading from the crankcase to the airbox with some liquid sitting on top of the crankcase. I think it's the "crankcase vent hose," but that's just what a bit of Googling lead me to. Backs up the oil idea, as well. If that's the case, should I have any concerns about having ridden the bike for a little while (maybe an hour, low speeds only) with the hose undone? Any issues with having the hose free for the last two weeks?

I'll check the oil level before heading out tomorrow, but I have a bit left from my last change so that shouldn't be a problem.

[n4mwd]

as long as your oil level is up, it shouldn't be a problem.
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[TBC]

^Thanks. Bike seems to be running just fine today.

Just got the tires installed. Thanks once again to everyone for all of the help!