A forum for owners of Yamaha TTR250 trail and enduro bikes!

petenz · Super Guru

Koso 34mm flat slide carb..

TTRfan · Super Guru

RE: 34mm flat slide carb..

TDVT · Senior Member

petenz wrote:
just ordered one of these KOSO carbs for the TTR....
they are a chinese copy of the OKO carb...
I have a OKO carb on my 77 Montesa Cota 348..
it totaly transformed the monty...
so at the prise of $39 theres not much to lose if it's
not as good as the OKO it's copyed from...
==> http://www.aliexpress.com/item/32mm-34mm-PWK-Carburetor-with-Power-Jet-Black-Color-Universal-Motorcycle-RACING-Carb-Scooters-dirt-bike/32227603941.html

-- Edited by petenz on Thursday 6th of November 2014 08:30:49 AM

I agree that this will be interesting. The TK is my least favorite part of the TTR. I looked at the link but it wasn't clear to me if this a pumper carb or not. (?)

But I do remember a link Brian posted of some rental bikes being run with non-pumper Mikunis so....

I was also interested with you comment about the OKO & your Montesa. I am rebuilding a '71 250 Bultaco Alpina & have been looking at a site here in the US that sells them pre-jetted, w/ manifold adapters, etc.

Sounds like it really helped your Cota. What did they come with stock?

petenz · Super Guru

TDVT wrote:
petenz wrote:
just ordered one of these KOSO carbs for the TTR....
they are a chinese copy of the OKO carb...
I have a OKO carb on my 77 Montesa Cota 348..
it totaly transformed the monty...
so at the prise of $39 theres not much to lose if it's
not as good as the OKO it's copyed from...
==> http://www.aliexpress.com/item/32mm-34mm-PWK-Carburetor-with-Power-Jet-Black-Color-Universal-Motorcycle-RACING-Carb-Scooters-dirt-bike/32227603941.html

-- Edited by petenz on Thursday 6th of November 2014 08:30:49 AM

I agree that this will be interesting. The TK is my least favorite part of the TTR. I looked at the link but it wasn't clear to me if this a pumper carb or not. (?)
But I do remember a link Brian posted of some rental bikes being run with non-pumper Mikunis so....
I was also interested with you comment about the OKO & your Montesa. I am rebuilding a '71 250 Bultaco Alpina & have been looking at a site here in the US that sells them pre-jetted, w/ manifold adapters, etc.
Sounds like it really helped your Cota. What did they come with stock?

sound like the OKO carb you are looking at for your bulty is from the same place

i got the OKO from for my cota 348.. ===> http://www.mid-atlantictrials.com/Sales.html

It is a pumper Carb..they call it a "power Jet"

TDVT · Senior Member

That is the same place. They have done a few Alpinas & as I have the earliest version, they are nearly identical to the Sherpa T anyway. Mostly just different gear ratios & a bigger seat I'm told.

Wondered about the "power jet" name, that would make sense.