It might be well worth your while to look around for a bike shop near you that has an ultrasonic dip tank to thoroughly clean all the little passageways in your carb. There is a shop locally here that does it, and usually gets $35-$40 to clean a carb. Here in the Northeast, the ethanol is the main problem, when the gas evaporates in the carb, the ethanol layers up, and clogs the smaller passageways. I use 1 oz. of Marvel Mystery Oil per gallon of Ultimate 93 octane gas, it deters the ethanol buildup inside the carb.

at this price why not try it.http://www.ebay.com/...=item2c5e398b19

condor74, on 27 January 2012 - 07:01 AM, said:

It'll bolt on, but that's as close as you'll get it without a bag - o - jets and a bunch more patience.

On your existing mixer, there is a possibility the needle for the main jet is out of another carburetor; possibly even the throttle valve itself. Either will throw off jetting up top and yet still be ok at idle / on pilot circuit. This would be unlikely, but possible.

For setting float height, I prefer to set it up while the carb is mounted in place on the bike. This eliminates any problems caused by suspension alteration, severe tire size changes etc.

Get the bike level front to back, side to side. This is critical.

Install a clear fuel line on the drain spigot of your carb. Make a 'J' shaped loop, from the drain rising up to the cap on the throttle cable @ carb. Keep the J shaped loop at the carb as short as possible without pinching off the line. Tie wrap it tightly to the carb

Turn the fuel on at the tank, slowly open the drain valve. Fuel will begin to fill the line you've just attached. It should stop rising when it reaches the height of the seam between the carburetor body and the bowl. If the fuel rises higher than the seam in the carb then stops, your height is too high. If it is more than a 1/8" lower, it is too low. If the line fills continuously and spills over, you have either a problem with the needle and seat or your has a hole in it (filling with fuel). This works with every float equipped Keihin or Mikuni I've ever seen.

hi guys. i was gone for the weak end so i havnt checked the thread.



i know i can get a cheapo carb, but it is not oem, and would probably cause more problems then it solves. of course i could get a used oem carb, but that would come with its own set of problems as well.

i am 100% sure i dont have a slide form another bike. i bought this motorcycle from the original owner barely broken in. the air filter was only slightly dusty when i got it, and had never been cleaned before. then i rode it basically every day for at least an hour a day for like 3 years, so it has a few hours on it. i never hand any real problems with it until now.

im not sure if i should just try out one of those non oem carbs, but its getting to the point where im running out of options.

is mikuni a good choice?? they seem pretty popular.


if they are good, what carb should i get. on ebay, i found 26 and 30mm carbs. will they both fit?? will one be easier to install then the other??

what kind on mods do i need to do to the throttle cable??

also, what kind of jetting do i need to do?? will the carb work pretty good out of the box???
heres the carbs


26mm http://www.ebay.com/...c#ht_3191wt_816

30mm http://www.ebay.com/...c#ht_3191wt_816

whats with these $30 mikumis??? are they real??? or are they selling fakes right out in the open. they have mikumi cast in the case........ the clone keihins dont have anythng cast in them. how can i tell if they are genuine mikumi or keihin??

The Mikuni-clone carbs usually have Japan - T/A on the lower right side of the carb body. I believe they are made in Thailand, under the auspices of Mikuni. An original Mikuni carb will have Made in Japan somewhere on the carb body.

so basically they are both mikunis, but one is made in japan, and one is not??? is the japan one worth the 100bux compared to 30?

i search for mikuni on ebay and they are all around 30-40 dollars. they all have mikuni cast on the outside, but they do have that japan-t/a thing too.

Mikuni does the same thing that Honda does with their outdated tooling and machining equipment; they sell it to whomever to use. Some Chinese engine manufacturers use this older, used technology to manufacture their engines, that is why the tolerances aren't as tight, or fitment is as good as Honda products.Certain engine manufacturers have no concept of the words Quality Control. The Company in Thailand (again, I think) probably has an arrangement of some type with Mikuni to use their name on the carb. Those clone carbs use real Mikuni jets, but they are hit-or-miss right out of the box. I had two identical carbs here at one time, with the same settings and jets; one ran like s**t, the other ran better, but not 100%. After spending a considerable amount of time trying to get both of them to work (to no avail), I ended up using a TrailBikes ShengWay 20 or 24mm carb.I think I even still have the Mikunis here somewhere, deeply buried in the spare carb parts box.

what should i do?? i dont exactly have a ton of money, so a 150 dollar carb is kinda out of the question. my stock carb is messed up. i did the float hight check but instead of using clear tube, i used a piece of normal tubing and lowered it until i saw fuel at the end. this was my plan, but as soon as i opened the drain and turned on the fuel, it ran all over even with the end of the tube above the float chamber aria. im not sure how the engine is not flooding out, or why gas is not gushing out the drain vent. the float works properly. this would explain the rich low speed tho.

im not exactly sure how these carbs work, so it makes it hard to fix lol.

does the pilot circuit control low speed, or low throttle position?? my problem seems to be that the engine does not have enough vacuum to pull gas at wot, at lower rpm.

MCRIPPPer, on 30 January 2012 - 01:15 PM, said:

Off-idle to 1/4 throttle is controlled by the pilot jet circuit, 1/4-throttle to 3/4-throttle is control by the jet needle, and 3/4-throttle to WFO is controlled by the main jet circuit, but, as I said back in post #13, these ranges overlap somewhat.

Isn't there anyone you ride with that has a similar bike with a similar carb that you could try on your bike, just to verify that it is, in fact, your carb? Did you try going to baseline settings like I also mentioned in post #13?

From what I can gather here so far, either you're trying to polish a turd, or your carb settings are so far out in left field that you're in the next county. If you don't want to be bothered trying some of the advice people have offered here, then it's a moot point to continue helping.

unfortunately, there is no one with a bike like this that i know of. i have tried going back to baseline settings and it was pretty bad. i had to rev it way up in order to go full throttle without it bogging out go dead. i have tried a different plug, checked valve clearance, changed oil (oil smelled like gasoline from sitting around with fuel vapor in the cylinder ), checked spark strength(it jumped about 1 inch easily), the only thing i can think of is that there is a passage in the carb that i have not found.


right now its the best it has been since i got it going again. im running a 35 pilot, 100 main, main jet needle on second from bottom groove, pilot screw at 1/4 - 1/2 turn. the bog is very minimal, but it is still bad when at really slow engine speeds, and the low end is all sputtery and rich. anything above idlespeed and above 1/8 throttle and it runs good.

it seems like it is slowly getting a little better just from riding it often. maybe something in the carb is slowly dissolving lol.

i put a bit of lucas oil fuel treatment stuff in (sorry, dont know the exact name off hand) it is supposed to help clean carbon and clean up fuel systems.

when youre done trying to figure this out, ive got a great oem carb with cable for 40$