Dasa FCR on a 05

[859davidt]

I have a Dasa 43mm FCR on a 05.Everything was good.But after taking it apart and cleaning it,it does not idle the same.Its either too fast or too slow.I lost the sweet spot some how.Anyone else ever experience this?

[chad502ex]

what are your engine mods? ported? cam? pipe? filter?

[859davidt]

Dasa porting,HRC cam,Dasa Pipe,13:1 piston,uni filter.Everything was fine until i cleaned it.It still runs good,just can't get that smooth idle back.

[chad502ex]

hmm,.. i've experience once that when the slide was removed the rubber o-ring gasket on the back of the black slide plate was not allowing proper seal of the black plate against the slide....

hope this helps.

:D

[859davidt]

Thanks.I will take a look at that.

[jshtex]

Did you take the slide out / apart?

If you did then check to make sure you put the flat plate (the cover for the box part of the slide) back on correctly. I have heard of folks having trouble when they put that cover on upside down. I think that might be the same part Chad is describing but a different problem.

If you look into the carb from the air box side, with the carb in the installed position, you should see an "M" stamped on the slide. If you see a "W" you have it upside down.

[chad502ex]

Originally posted by jshtex
Did you take the slide out / apart?

If you did then check to make sure you put the flat plate (the cover for the box part of the slide) back on correctly. I have heard of folks having trouble when they put that cover on upside down. I think that might be the same part Chad is describing but a different problem.

If you look into the carb from the air box side, with the carb in the installed position, you should see an "M" stamped on the slide. If you see a "W" you have it upside down.

great suggestion about the M... that plate also has a rubber seal on the back where it meets the slide... that rubber seal it critical for air flow when the slide is shut.

very good contribution jshtex. That may really help him out.

[859davidt]

jshtex and chad502ex.Thanks!That was it.Plate was upside down.20 years of atv racing and you learn something new everyday.The only thing i am concerned with is that i could only get it to go down in there with the plate facing the motor side v/s the air box side.I got my 2nd carburator back from Dasa yesterday and it is facing the motor side too.Do you know if it makes a difference?

[jshtex]

I am glad it helped.

Before I posted above I checked my carb, just to make sure it was what I thought it was. Plus mine happened to be sitting on the bench beside me anyway, but thats another story.

I guess it is possible that I was looking into the engine side, but I thought about that and I "think" I was surely looking in the air box side.

Another posibility is that when I took ours apart to mod the spring mount to make the throtle pull softer maybe I put my slide in backwards???

I happen to have another YFZ with another FCR so that hasn't been touched so I will take a look at it.

[859davidt]

Another thing maybe you can help me on is Hot Start.I never had it hooked up before and decided to put it on.There are no threads for the cable to screw on and the hole on the carb looks solid.Is it possible that someone has plugged this somehow?I see no air passage in there what so ever.I bought it used off e-bay.

[chad502ex]

the black slide plate is designed to face the engine.

[Colby@C&DRacing]

Sounds like the carb you bout is off of an atv with electric start they don't come machined for the hot start. I have a guy that we do a lot of stuff with that cam machien that is if you need it. www.glanninnovations.com