Topic: Vintage CR31 Carbs

[H2Eric]

Some of you CR gurus out there must have come across this problem.


I acquired this set of carbs from Kurt Liebman some time ago, the accompanying inlet rubbers came from a different source. The rubbers fit nicely on the carbs though I may have got the things on the wrong way round in the pic, but subsequently removed. The rubbers have no numbers on them like the standard items, just a letter A, B, C, and D. The snag is that the inlet rubbers don't fit the inlet stubs on the back of the cylinder head because they are simply too big. Hmm, something definitely amiss here. Is there a simple solution or have I got the wrong parts?

Thanks
Eric

[kmb69]

Maybe for the F2 head? If you want to sell them and get you some proper inlet manifolds, let me know.
Keith

[voxonda]

Looks like they are intake rubbers for a DOHC 750, they used the same CR31's. And their spigots are bigger.

Rob

[lordmoonpie]

I used standard manifold rubbers on my CR31s - they are a total bugger to push on the stubs but once on they are fine...

[H2Eric]

Maybe for the F2 head? If you want to sell them and get you some proper inlet manifolds, let me know.
Keith

Thanks Keith
PM sent

Eric

[kos]

Looks from picture that carb spacing is uneven IE:  distance between 1 & 2 is not same as between 2 & 3.  If that is case those are CR900 carbs which are made original for Z1 Kaws and then later fit same spacing on Suzy 750/1000"s as the Suzy motor was a copy of Z1.

If those rubbers were from DOHC, they would be huge and not even come close to fitting.

If carbs are CR900 you need Mikuni 29 smooth bore rubbers and I have those in stock.

Mark @m3


KOS

[voxonda]

Mark,

Would the 29 smoothbore rubbers fit the VM33's?

Thanks, Rob

[H2Eric]

Looks from picture that carb spacing is uneven IE:  distance between 1 & 2 is not same as between 2 & 3.  If that is case those are CR900 carbs which are made original for Z1 Kaws and then later fit same spacing on Suzy 750/1000"s as the Suzy motor was a copy of Z1.

If those rubbers were from DOHC, they would be huge and not even come close to fitting.

If carbs are CR900 you need Mikuni 29 smooth bore rubbers and I have those in stock.

Mark @m3


KOS

Mark
Well spotted, the spacing is uneven just as you say. Will the Mikuni 29 smooth bore rubbers line up with that uneven spacing or do the carbs have to be adjusted to make the spacing even, which doesn't look easy at first glance.

Eric

[kos]

Yes, The Mikuni manifolds make the uneven spaced carbs line up and work just perfect. Bolt on and these are new!

Mark  @ M3

[kos]

Mark,

Would the 29 smoothbore rubbers fit the VM33's?

Thanks, Rob

Well, they fit the  KO head from 1969-1976 and have the same spacing as kaws an suzukis, Spigot size is same as 31mm early keihin race carbs (34mm  inlet side of carb) so the rest is up to you as I  do not ever use Mikunis.

KOS