Yamaha TRX850 Enthusiasts Forum

I have only been able to find this type of screw for KEIHIN FCR carburetors ...



Anyone know if there are hand adjustable fuel mixture screws for TRX ´s carburetors (MIKUNI BDST38 / 2)???

Item reference??

Place to shop on the web?

Thanks guys!

If you`re in the UK speak to Allens:

http://www.allensperformance.co.uk/

IF they`re available those guys will know.

If you find some, post it up, they are an absolute bitch to adjust!

M.V. wrote:If you find some, post it up, they are an absolute bitch to adjust!

Which part would it replace?

nº 27 ... but only mixture screw ... on this diagram nº 27 includes besides mixture screw, spring, o-ring and washer to fit it on the carb ... although a kit with all the elements (like the photo of my first post) also would be ok!

Looks like #27, are you going to whip a couple up Kayla?

Edit: Yep, #27 Pilot Screw Set, according to the parts manual.

M.V. wrote:Looks like #27, are you going to whip a couple up Kayla?

Edit: Yep, #27 Pilot Screw Set, according to the parts manual.

I'll have look if I can get the sodding Buell out of the shed to get to the parts box

Please remember he wants these for the FCR not the std carbs. Depending on price I will have a pair too.

Kenny wrote:Please remember he wants these for the FCR not the std carbs. Depending on price I will have a pair too.

No. I want it for standard carbs (MIKUNI BDST38 / 2) !


... for KEIHIN FCR you already can find in a lot of these on internet ...

pininfarelo wrote:

Kenny wrote:Please remember he wants these for the FCR not the std carbs. Depending on price I will have a pair too.

No. I want it for standard carbs (MIKUNI BDST38 / 2) !


... for KEIHIN FCR you already can find in a lot of these on internet ...

Not true, you can find a bunch for MX carbs but they won´t clear on the TRX....already been there when buying my FCR´s

Killerwhale wrote:

pininfarelo wrote:

Kenny wrote:Please remember he wants these for the FCR not the std carbs. Depending on price I will have a pair too.

No. I want it for standard carbs (MIKUNI BDST38 / 2) !


... for KEIHIN FCR you already can find in a lot of these on internet ...

Not true, you can find a bunch for MX carbs but they won´t clear on the TRX....already been there when buying my FCR´s

The photo on my first post, are screws to fit on KEIHIN FCR carbs ... they are used mainly on dirty bikes (I use one on my YAMAHA WR 250 F) ... If your looking for "FCR mixture screw " can find a lot online, but I'd like to find it for the standard carburetor (MIKUNI BDST38 / 2) of the "TRiXies".

My only thoughts are why do need them? the only time you should be adjusting is on a dyno, to set up for optimum running. Dirt bikes are different and also single cylinder!

Dave E

slow codger wrote: My only thoughts are why do need them? the only time you should be adjusting is on a dyno, to set up for optimum running. Dirt bikes are different and also single cylinder!

Dave E

It is true that this is not necesary to be playing all the time (in contrast to a dirty bike), but would provide much more comfort when you had to do it (not necesary remove the carbs) ... and much more precise adjustment if you do not remove the carbs and try to adjust with special screwdrivers or something like this ...

So you can tune it by feeeeel, like on a Ducati

I prefer to tune while it's running, but it's nigh on impossible with the TRX. On my old CX500 it worked a treat, it's a bit like syncing the carbs; you can tune each cylinder individually & they run a bit smoother.

wouldnt be too hard to make a set honestly. I got a spare set of mikunis here i can inspect / measure if theres enough need.