On taking out and cleaning my reed valve i noticed the metal stoppers are different.
One is at a slightly different angle then the other? I tryed loosening and tightening the screws but it made no difference. Also it makes one side of reed flaps harder to open then the other. Is this normal?
My bike also stutters at top speed, i taught it was a fuel issue. I just after having a look and it seems one side of the petals are thicker then the other. Look at the second picture down and on the right side.
These are also the ones that open very easy.
My stopper height is 11mm. It says in the Haynes that it should be 6.8mm
But that seems way too small of a gap.
-- Edited by vtec2008 on Monday 4th of July 2011 12:07:15 AM
-- Edited by vtec2008 on Monday 4th of July 2011 02:34:22 AM
-- Edited by vtec2008 on Monday 4th of July 2011 02:35:07 AM
When I had my reed block off a few weeks ago as put racing reeds in, mine looked just like yours 2 different bends etc, and I dont get stutter at high revs mate, but if your indoubt now you have the block out do line them up how the manual says and see how the bike is I take it looking at that pic in the manual they both have to bend at the same MM? then report back here, for future reference
Well at the moment the engine is in my brothers house and the bike at mine. Got a rebore and just waiting on other parts in order to put it all back together. Will report my findings when done :). Its a bit confusing all the same lol.
Also which way does the reed vlave petals face when installed to the engine? One side has thicker petals then the other. Do i face the thicker ones down?
-- Edited by vtec2008 on Tuesday 5th of July 2011 08:09:08 PM
My thoughts exactly! 6.8 has to be a missprint, Well i have them both now at 11mm as the one that looked ok was 11mm. So i bent the other stopper to 11m also. BTW which way do i put in the reed valve in the engine? Any certain way to face the thicker side petals?
6.8mm quoted by Haynes is the same as what Yamaha say. This opening is too small for performance and will be restrictive for any carb bigger than 26mm. Best thing to do is open up the stops 1mm at a time until it stops running cleanly, which is when the reeds will be bouncing on the seats. I wouldnt recommend doing this with steel reeds due to metal fatigue and the risk of one breaking. Non metallic reeds usually are better on fatigue and if they do break it shouldnt do too much damage to your engine on its way through.
Yeah i will try different opening sizes when i get the bike running. Its funny how the stoppers got bent in the first place because this is the bikes first time been pulled apart since it left the factory. Original yamaha gaskets were still in. So nobody has been playing around with it.
I cant find in the manual or anywere to which way to put in the reed valve in the intake port. Do the thinner petals face the crank or the flywheel?
I just sent pm's to everyone on ebay selling a DTR reed valve asking them to measure it. lmao! Got 5 replys with between 10 to 11mm. Im thinking of buying some Boyesen duel stage reeds from pjme, are they any good? Rejet?
-- Edited by vtec2008 on Wednesday 6th of July 2011 04:58:02 PM
boyensen have had a good rep since they established, probably wont make much difference unless you tune up you reed block E.g make the windows bigger, also show a pic of your inlet manifold , does it have a big lip on it
Heres a picture of the intake it has that lip on it. I just scrubbed the whole engine to death yesterday you could eat your dinner of it now . My girlfriend just loves the smell of stale petrol and wd40 coming from under the bed lol.
HAHA **** i taught you ment.....ah well. No i havent touched the rubber inlet. i heard too many stories about people messing up the engine cutting out that rubber lip.
my friends dtr is a 2001 reg bike made in 2000-model and had this reed setup ...its probs yamahas cheap atempt at restriction ...as it causes flutter at proppa revs
if you look at any other reed petals (after market or not ) ...they match because of frequency of reed valves remaining the same
the reeds in my 1990 were standard when i bought the bike just like the rest of the bike 100% genuine and dusty/rusty/standard
both reeds are the same and this bike has it
if your reeds are opening sooner on one side you are only getting full charge velocity for half the time of the port opening ....this is not good for fluid dynamics ...this slows the bike at top revs and makes it stutter/flutter
crankcase compression is just as important as combustion chamber compression but they are two very different things
without reed timing your crankcase compression is messed with and you become restricted by compression timing
It makes sense that it could be yamahas attempt at restricting the bike. Im not gona bother putting back in the stock reeds even after ive bent the stoppers to their right postions. Im going to buy the Boyesen duel stage reeds.
Things ive done so far
1. Cylinder bored to .50mm plus honed with ports dressed. Also skimmed head. 2. New piston, rings and top end bearing 3. Reed switch out of clock. 4. New..ish 3MB front expansion chamber now derestricted (little pipe cut out) 5. New D.E.P silencer. 6. New Coil 7. New airfilter 8. New sparkplug 9. Carb cleaned with carb cleaner. 10. New front and back brake pads
Few more things to do also. BTW isnt all dtr caseing like that?
no man the casings have flaws from the factory but some line up better than others
yours just seem well out
all the other bits sound awsome man ...you seem to know what your doing for the engines sake.....we like a proppa hone and the ports all shamferd ...it creates longevity
and brake pads are always a good idea
and the old exhausts do have it so you got no probs there...but is your dep the old version too as they are tuned to work together and make some real difference as the stinger is part of the tuned length also
dont get me wrong im not trying to know it all but i have been into this since about 1988 and have read and reserched all things moto since then ...not to mention all the bikes ive built
wierd i know but its a passion of mine...and im not trying to mislead anyone with their bike
check out the first start vid of my mates bike 2001 reg 2000-model its up loading now so give it a minute
(dtdans cursed rebuild ) mmmmmmmmmmmmm 2 strokes love it
-- Edited by GADGET on Wednesday 6th of July 2011 11:55:28 PM
The intake port is the only thing that seems out of alignment. All the screws and bolts match up. The reed valve cage seems to fit with a perfect seal so im not bothered. Heres another one that looks like mine.
Maybe all the german imports have it. The DEP is about 3 years old, got it from a m8 who never used it and was stored from new. It has to be better then the stock silencer right? To be honest im new to this, ive always been very mechanically minded. I also built water cooled gaming pcs a while back. But my real passion is bikes, cars, engines, and electrics. Im always been haunted by people to come fix this, and come fix that lol. im always bloody fixing something lol.
Christ! If it wasent costing me enough money as it is i now have to add 2 new suspension oil seals and a rear brake caliper build kit to the list..ARRRRRHHHH
link below
. My girlfriend just loves the smell of stale petrol and wd40 coming from under the bed lol.
?????
