fitting a mikuni to 75 mc250

[Kevin Jury]

Hi all, I want to fit a mikuni to my 75 ktm mc250 and was wanting to know what to do for the air box to carb rubber boot? is there an existing boot of some other bike that will do the job. Thanks for any input you can offer. And happy new year to every one.
Kevin.
75 mc 250
79 mc 420
80 mc 125
81 mc 250

[Mick Milakovic]

Kevin, I use a 34mm Mikuni on my '75 Harescrambler.  I use radiator hose from an auto parts store to fit the carb to the intake, and cut about 3/8" off the intake to give more room for the carb to fit.  The airbox boot is a very tight fit, but with the use of a heat gun I can make it pliable enough to fit the carb.  Hope this helps,

Mick

[Dale Sonnenschein]

I am doing the same to my 75 250. I wonder if the 34 and 36 have the same diameter inlet from the airbox. My boot has to stretch ALOT to fit mine. I haven't tried it yet but its way smaller than the carb.

74 puch 175 SD
73 Husky 360 WR/RT
75 Penton 250
10 ktm 250xc
02 bmw r1150r

[Mick Milakovic]

Dale, I believe Thom Green (tomale) used a 34 bored out to 36 for better flow for the same reason you are experiencing.  He got more air flow with the advantage of a smaller carb body.  I'm not that fast of a rider (more interested in bottom end) so the larger carb was not necessary.

Mick

[Dale Sonnenschein]

Mick, I read some place here that he used a 34. I almost got a 34 and was going to see if I could get it bored to 36, but I bought the 36 instead. I have a couple ideas that i will try this week. I'll post my ideas if they work out.

74 puch 175 SD
73 Husky 360 WR/RT
75 Penton 250
10 ktm 250xc
02 bmw r1150r

[Big Mac]

Type MIKUNI into Search/Penton Talk/Subject. Scores of threads.
Start here: http://pentonusa.org/forum/topic.asp?TOPIC_ID=13179&SearchTerms=mikuni,

Happy adapting.