problem with 38 pwk

[45 lt80]

Putting a 310 prox cylinder in a 86 trx250r stock frame. When i was fitting the 38 pwk, a spacer plate, and boyesen rad valve. the carb. was hitting the top of the shockbrace and it wouldn't fit the connecting tube to the air box. This the set up I had on the stock cylinder. Is the prox cylinder different from the stock cylinder. ..


45lt80

[mfr422]

45lt80,
The angle and location of the intake is slightly different on the pro-x cylinders. You can try a reed spacer or on my buddy's R we made a spacer for the back of the intake boot to space the boot foward so it would reach. The angle of the rad valve is different also and this only makes the problem worse and makes the carb hit the frame. This also happens with the stock intake boot but it's not quite as bad. The pro-x cyl's angle points the carb right at the frame. We heated up the boots and used the spacer to fix it but his carb still rubs on the frame. Oh, btw his is an 86'. It doesn't hit as bad on my 88' but I still have some wear tape on the frame where it rubs. hope this helps, Roost ON!!

[C-LEIGH RACING]

That Rad Valve your using, it a TRX model or one for a CR250R dirt bike because there is a difference in them.
The CR Rad Valve, the tube intake part of the reed is shorter & will cause the filter tube mounting problem like your having.

Normally, with the Pro-x cylinders, you dont have any carb issues unless a CR250R reed & intake is used or the Boysene CR Rad Valve or the cylinder kit is for a stroker & has a real thick spacer plate.

There were some old first cast Pro-x cylinders, where the casting was different in the reed chamber area, was shorter, but newer models that has changed & has added lenght.
Neil

[45 lt80]

A new day. Got the reed spacer, rad valve and the carb. on the bike. I couldn't get the air box tube on. Can I move the air box back to get room.


45lt80 :mad: :mad:

[Aceman]

Get rid of the reed spacer.

[garrettagr]

i had the same problem with mine. i had to use a CR boot with no reed spacer. i still had to wrestle with it though to make it fit.