Mikuni carb service/repair kit?

Discussion in 'The Garage' started by Bongolia, Oct 27, 2013.

  1. Bongolia

    Bongolia stop acting

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    Guys, hoping somebody here can help out.

    I have a 2005 Suzuki TU250G 'Grasstracker'. It is a carb model not FI. Mikuni BSR 32 CV type

    Tonight I noticed gas under the bike. The fuel tap was in the off position.

    Looks like I have both a leaking fuel tap and a carb issue with either the float or the needle valve

    I'll pull the carb and tap next weekend and check and clean. Also looking for a service kit and I've drawn a blank for this carb. Any ideas?

    This isn't a US or Euro bike (Jap home market) but the carb was used on a few Suzuki models
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  2. anotherguy

    anotherguy Long timer

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    I'd repair the fuel tap before tearing into the carb. Gravity feed carb float needles are only designed to handle 2 PSI max and if the tank is full enough it can overwhelm the needle. I might remove the needle/seat and clean/inspect before spending money.
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  3. Bongolia

    Bongolia stop acting

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    Thanks, will do.

    I'll be pulling the carb anyway as it isn't set up right. Starts no choke, idles a bit too high, and a bit of a lag when rolled off on the throttle for it to settle to an idle.
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  4. rjsurfer

    rjsurfer Been here awhile

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  5. Bongolia

    Bongolia stop acting

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  6. rjsurfer

    rjsurfer Been here awhile

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    These two Yamaha parts take care of the the front side of the petcock,

    3aj-24534-01 O ring
    3ac-24523-00 Smily face

    The backside is a diaphragm, I believe that it can usually just be cleaned up......

    Ron W.
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  7. Bongolia

    Bongolia stop acting

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    [​IMG]

    Stripped the petcock and carb. Petcock smiley has a nick in the surface which is allowing gas to trickle through to the carb.

    Stripped the carb too, needs a good clean inside. This diaphragm looks a bit odd, is this normal or do I need to replace it? There are no holes or tears in it.

    Thanks

    R
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  8. rjsurfer

    rjsurfer Been here awhile

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    They all look like that, to be on the safe side put some 303 protectent on it to keep it from cracking. You can get the diaphragm from any Suzuki dealer and keep it as a spare. You can change them out just by rotating the carb sideways, no need to remove carb.

    Ron W.
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  9. Bongolia

    Bongolia stop acting

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    Cheers Ron, you're the man. :bow

    Any ideas on how to get the pilot screw out? No cap on this model, but looks like it is jammed in place with a chewed up head :baldy

    Local heat on the surround and an impact driver?

    Also in the longer term I'm likely to change the carb, is there a standard mikuni swap for this?
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  10. rjsurfer

    rjsurfer Been here awhile

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    Well, I'm finally out of answers:1drink

    Usually the impact approach is the best, as far as a carb swap I don't know of any.

    Best of luck........

    Ron W.
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  11. Crisis management

    Crisis management Latte riders FTW!

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    Re; pilot screw, be careful with the impact driver as they are very soft metal (in case you hadn't noticed), I have had some success with a small drill then tapping a torx bit into the hole and backing it out with a rachet. Torx bit as they have small, multiple deformations that provide good grip without deforming the screw you are trying to extract.

    Carb change,why? The CV is a great carb for most purposes, a flat slide or pumper carb has some advantages in race conditions where it runs at full throttle mostly otherwise the CV performs better.
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  12. Beezer

    Beezer Long timer

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    left handed drill bit for the stuck screw.

    you will be appalled by the price of a new diaphragm
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