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X-18 mikuni 22mm install???

5943 Views 24 Replies 4 Participants Last post by  EPR
Hey folks, im a total noob, recently bought a cheap x18 that needs some work and im attempting to learn on the job so to speak.

So i just purchased a 22mm mikuni carb, blue 5 pin cdi box, racing coil, and about to purchase a UNI air filter.

the UNI i believe i need is a 1.5" dual right? do i also need an adapter?

so are there any instructional threads on installing this stuff here on the forums?

any help would be appreciated thanks!
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If you run into probs just ask but I posted on your last thread
The outer ring of the 22mm carb where the air filter mounts is 38mm I believe, I had to stretch my 35mm, X18 filter to get it over the bigger lip.
i read the mikuni uses a 1.5" uni air filter... sound about right? also drgn for the uni did u use a straight or a curved filter?
I used straight but a curved gives a few other possibilities with the carb facing forward either should work ok
just a heads up, if you got the same mikuni as i did, you will need a swivel plate to mount the carb off center, as the stock manifold makes the carb hit the valve cap on the head.....found that out the other might...LOL i got a real mikuni vm22... and my swivel plate showed up, and is going on tomorrow...LOL
47, 1.5" is 38mm, so there right. Look at my 125cc ATV 25mm carb change photos from yesterday it has a piece of a golden swivel under the carb. It had a O ring for the head port, but I fill the groove w/ RTV and put a paper gasket on both side.
Hmm once again my bikes are different lol I must have a batch of messed up x18s my carbs bolted up to the manifold facing forward and had a very little room the bowl just about touches the top cam cover I guess I just got lucky so far
Hmm once again my bikes are different lol I must have a batch of messed up x18s my carbs bolted up to the manifold facing forward and had a very little room the bowl just about touches the top cam cover I guess I just got lucky so far
My intake goes forward too... And the carb almost hits the valve cap too... A mikuni vm22 DOES.....lol
See the gold colored swivel under tne intake manifold, mine is off set 1 to the right. I had to get 2 flat head M6 x 1.0 x 30mmscrews cause the stock ones where way to short. I did not use the bottom O ring either, I put RTV silicon in the groove and used a cut out center paper gasket.


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Thats pretty much how mine is gonna be.... I may go two to the right, so i can run an air filter that i already have laying around....LOL
ok, well my carb should be here tomorrow so i guess i will see then what i need. do you think maybe the differences are due to the year of the bike? i have no idea what year mine is but i would suspect 09.
thanks again for all the input guys, i would be lost without it LOL
Should be a tag with all the info on the front corner of the frame, things like model, year, engine size, etc....
For some reason all mine were 2007 models maybe there were a lot made that year but the china people do all sorts of weird things if they didn't have the right intake they'll grave one from over here that works for now lol
Maybe no plate like mine lol never know with these bikes
houston we have a problem...

parts arrived today but...

okay, put on the coil and attached to spark plug, it snaps on but then has some wiggle to it. does that happen to anyone else? also the green wire was connected to the bike and i taped it to the green connector on the coil (see pic) is that right? pic shows before i taped it, wasnt starting then either.

i attached the cdi box and clipped in, removed the old one.

and the carb... i had to file down the bottom a little bit cuz it was JUST a bit to long, but i got it to fit securely. then i used the stock throttle cable and attached it and there is a TON of free play in the throttle before it engages. do i need to replace the throttle cable? also the bike will not start now, kick or pop start (it always pop started easily before) and i have what appears to be gas leaking from the mid way point of my exhaust pipe (see pic)

any tips? thanks

also thinking about buying an aluminum throttle w cable set:


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At first the carb wont want to start for some reason... Mine was the same way.... Does it pop off on starter fluid? Do you have decent spark at the plug?
Oh and for the cable, theres a barrel adjuster on your throttle under the rubber boot coming off the handle bar....
thanks bogieboy, i actually went and played w the carb where the throttle cable goes in and here i hadnt inserted the pin and valve and spring ALL the way down. once it went all the way in the thottle was fine and it started right up. mission accomplished! now i need an air filter
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