'83 250CR dropped off at Jemco

I must have a cr cylinder then... Because mine is doughy nothing and then BWAAARRRRGGGGGG All hell breaks loose. Sure makes you appreciate power valves! Climbing snotty hills is interesting, to say the least. Poor old clutch....

Hey Picklito,
Where did you get the Keihin PWK flat slide?

I would love a carb with more low speed air velosity for easier starting on my 1981 430 CR!

Does power now make the inserts for that carb?

HuskyT - Only applies if you're doing AHRMA in classes below Ultima, doesn't matter here in local Texas races either.

Hey Husky T,
What Flatside are you considering?

Sorry not to have a link but for the Pacific NW go to Vintage Dirt Racing or "Hammer and Tongs" for their rules. HighDez- I went to a 3.0 slide in my 82-430xc, easier starting and crisper off of bottom. alot more Idle mixture adjustability.

I had it... from my collection of old KTM stuff. Either the 38 or 39mm works fine. It does have snappier response and better fuel economy than the Mikuni round slide. I can't say it starts easier, mainly because I've always thought the Mik had a good choke circuit and they always fired off nicely in my opinion. I don't know about the power now inserts. I don't buy many "hop up" parts.

installing new TMX 38mm Mikuni flat slide on mine today, breaking in this weekend. Will let you know

oops, this TMX won't fit in the space, WTF! I'm running a Mossbarger reed cage (+ 3/4") with a cut down air boot (- 1/2") and there's not enough room to squeeze it in between the air boot and manifold.

Option 1- return it or option 2 swap back to the stock reed cage and hope it fits?

Hey Leftcoast,
What is the dimension from the front spigot the the rear air horn?

Is it 100mm? it may be an older TM model.

In my Sudco tuning manual it shows a TMX38-27 with an overall lenght of 76mm

That is like 15/16" shorter so you wouldnt have to go back to the stock intake.
If you do i will buy the Mossbarger from you.

Sudco 323-728-5407 TMX38-27 $217

The rear airhorn is the same dia. as the stock VM mikuni round slide62mm.Front spigot is 44mm which is only 1mm or .039 in which you can use a heat gun or hair drier to warm it up.

Hope this helps,let me now what happens as i am looking to do the same thing to my 430 to aid in cold starting.

Are you happy with the Mossbarger set up?

How did it change the performance and starting?
Thanks

Highdez- that's the width i think, the length is 100mm; the manifold and airboot dims are the same between the vm & tm series (per my sudco manual)

love the m-barger but if it doesn't fit with the tm then i'll pm you

shouldn't be a starting issue cold or hot with these bikes, see an earlier thread with tips (quite simple really)

Any update on the exhaust at Jemcoe ?

Not yet but expect in next week or two as several also have called them about pipes as well.

Another reason, other than cylinder porting, for the difference in power delivery between the '83 CR250 and '83 WR250 would be the stock pipes . The CR pipe above has a shorter rear cone section and longer stinger section , when compared to the WR pipe in the same picture. The Cr pipe is also noticeably fatter from the first weld , right up to the start of the stinger .

Pipe Complete ??

Rhett - has Jon finished your pipe?? Jon is working on a one for me as well...rb

Hey RB how's it going ? Suppose to be done this week. Which one is he doing for you ? The '76 Husky 250 ?

Wow! That's a great comparison photo. Thanks for posting that. My WR pipe looks just like the WR pipe in the photo and, as I said, that bike is strong and broad. I hope someone can bolt a WR pipe onto the CR and see what it does.

That bike (79 WR) was stolen out of my trailer at the Omni Hotel in Houston...not good. I am re-building a 83 250XC...the photos looked good but it is the all time record pile...bad shape. I am starting with the frame and re-doing everything...not my intention but no choice. So Jon is working up a pipe from the one that he built you...front mount is different, and I am going to bring my bike down to Jon and get that worked out. Jon is a great guy is built my exhaust for my 79 C&J...New alarm on my trailer, first bike theft that I have ever had.

rb