Just asking, i can fit reeds in a PRe 75 Cr125 and its legal right ?

[Freakshow]

Just asking, i can fit reeds in a PRe 75 Cr125 and its legal right ?

[JohnnyO]

It should be legal Freaky.. you could buy a Gem reed block in 1974 for a 125 and 250 Elsinore but who knows with the rules nowadays.

[jimg1au]

freaky
yes you can but must NOT BE V FORCE
a gem is ok

[DR]

A GEM reed setup will enhance the CR's low end power but it's a trade off and you may find it'll lose a little off the top I tried a GEM reed on my TM125 when I first built it and that's basically what happened.

[TT5 Matt]

Doc if your tm lost power up top than the reed valve and manifolding are acting as a restrictor, maybe a larger r/valve out of a 250 would give increased flow

[Freakshow]

I think the Gem Type interreed, on a TM v's a CR on Alchy will be a little hard to compare, plus it might actualy fix the Cr125 'must run at 60,000 rev or nothing" problem anyway 

Been messing with it and its been about the same line drag as the TM 250 on petrol, but against the other Cr's on petrol and Piston port its been 4 sec faster per 30sec laps, so looks to make a big differance in combination.  Just wanted to be sure i wasnt crossing the line, i assumed it was fine as other bikes ran Reeds in Pre 75 so basically your just transferring the technology across. 

Thought it was just worth checking before i committed to saying it was 110% legal ( i scrutineer on the classic line and dont want to shoot myself in the foot and look like a bigger peanut) 

[DR]

30 second laps ..obviously we are talking about flat track where it's a HP thing but the flow problem remains static no matter what fuel you run. I think you'll find the CR will develop more top end power without the reed regardless simply due to the reeds messing with the inlet flow especially at high rpm.

[jimg1au]

to get it to work properly you need to get the barrell ported.you cant just bolt a reed valve on a piston port motor and think it will work.
look at the difference between you rt1 and yz to see what i mean.
jim

[Rossvickicampbell]

Freaky - Jim is right in that it is not just a bolt on.  I believe two types were available - mossbarger and Gem.  I had the Gem on my 250 but it also needs porting and windows to the piston as well to get maximum benefit.  Doc - my well set up 250 absolutely flew with the Gem set up - made a huge difference to stock.

regards

Rossco

[DR]

I was actually going to say it isn't as simple as bolting it on but I assumed since the bike was running alcohol that the motor would probably be extensively ported and running a huge carb anyway

[Freakshow]

ported with 36mm MUK   

i know it works, i just needed to be sure its legal in case people ask questions

[micks]

moms 18.6.04 c)no reeds valves perrmitted on machines up to and including pre 1970 class

[Lozza]

freaky
yes you can but must NOT BE V FORCE
a gem is ok

There is no restrictions or rules to cover reed cages themselves.

[Rossvickicampbell]

Lozza - V force by design maybe but not V Force by make ie later?  

[firko]

You can run a reed cage aa long as it's a period piece of equipment. GEM, Mossberger and even a DT/MX Yamaha reed block welded to the Honda barrel is acceptable. I'm certain you won't get away with later setups unless you're a master of disguising your work  .