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I bought a RH side lower from a 400C or D, to be used on my 350A. Just because I think it looks better with the caliper behind the fork leg, and there is less problems using a 1 piece brake hose with that setup, without conflicting with a TZ type fiberglass front mudguard. Will get tis done whenever I get home from this hitch at sea.
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They were “in the wind”.  PO must have figured not needed. I did rebuild the pump fully and had lots of fun with that....
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Aircooled RD Tech Help 250cc and Above / Re: STD reeds to Boysen Reeds
« Last post by DVSRD on Today at 05:45:45 AM »
I never intended to claim any massive performance increase from changing reeds. Just pointing out the development since the 70s. And Ed E. does in fact  recommend YZ reeds even for stock RDs. Just at the beginning of his article..

Another argument for fiber reeds is availability. I doubt that original steel reeds are available from Yamaha anymore. Original YZ125 reeds are available.  Used reeds, even if they look good, will have been subjected to an unknown number of load cycles. That means there is a risk of them breaking from metal fatigue. I would not take that risk, knowing the cost of engine rebuilding.
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Aircooled RD Tech Help 200cc and Below / Re: Disc brake feel 125dx
« Last post by DVSRD on Today at 05:34:01 AM »
Just had a look in the manual and now understand what you mean Dave. Im guessing the pins might be seized either fully or partially.
Will have to try taking the wheel off and seeing if theres any movement on the caliper body. Im guessing that even without the disc restricting movement there is only a very small amount of travel.
The travel must neccessarily be a bit more than the thickness of the brake material on a brand new brake pad.
So at least 5  to 6 mm. You should pull the caliper apart, clean up the pins and their bores, and grease lightly. The pins should slide with little resistance.
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Aircooled RD Tech Help 250cc and Above / Re: STD reeds to Boysen Reeds
« Last post by tony2stroke on January 18, 2019, 11:24:34 PM »
Didn’t mean to light the blue touch paper guys ...... anyway started the job this afternoon, going to fit the Boysens less stop plates as recommended. It’s a 250f, large canned allspeeds, experimenting with rd 350 rubbers and boost bottle. Power was good already 6000 plus just trying to get a better response lower down the range. Will report the effect of change. Thanks to everybody commenting .... it all helps Steve

You could leave out the bottom gasket and use Threebond 1215 instead to seal, this would drop the cylinders by around 0.4mm (though check your squish then) then raise transfer ports by 0.4mm giving less exhaust lead (blow down), this should give you more low down power at the sacrifice of top end, its all a compromise, you can't have it all.
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Aircooled RD Tech Help 250cc and Above / Re: STD reeds to Boysen Reeds
« Last post by tony2stroke on January 18, 2019, 11:13:14 PM »
If the steel reeds fail, your engine will need a rebuild.

YZ125 reeds work well.

Moto Tassinari RM125 reeds are supposed to work once the center is bored through.

Just out of curiosity, have you personally ever had a steel reed fail ?  Personally I have never had any fail, but I have had fibre reeds fail, I am just wondering that's all.
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Aircooled RD Tech Help 250cc and Above / Re: STD reeds to Boysen Reeds
« Last post by ~JM~ on January 18, 2019, 10:44:26 PM »
If the steel reeds fail, your engine will need a rebuild.

YZ125 reeds work well.

Moto Tassinari RM125 reeds are supposed to work once the center is bored through.

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Aircooled RD Tech Help 250cc and Above / Re: STD reeds to Boysen Reeds
« Last post by Rimby_ding_ding on January 18, 2019, 10:12:15 PM »
Didn’t mean to light the blue touch paper guys ...... anyway started the job this afternoon, going to fit the Boysens less stop plates as recommended. It’s a 250f, large canned allspeeds, experimenting with rd 350 rubbers and boost bottle. Power was good already 6000 plus just trying to get a better response lower down the range. Will report the effect of change. Thanks to everybody commenting .... it all helps Steve
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Aircooled RD Tech Help 250cc and Above / Re: STD reeds to Boysen Reeds
« Last post by tony2stroke on January 18, 2019, 09:55:02 PM »
seems talking about reeds are like talking about pistons on here now   :o  :D :D :D :D

horses for courses I think is the saying chaps.
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Aircooled RD Tech Help 250cc and Above / Re: STD reeds to Boysen Reeds
« Last post by 5port on January 18, 2019, 09:35:15 PM »
Here are a few ideas from Dale Alexander, " I like metal reeds, so crucify me!"  ;)
And, "First off, I feel that the RD, RZ series engines do not have the port time/area needed to fully use any carb above 34mm to its full potential without suffering serious holes in the powerband and driveability problems. In maximum power applications with minimal regard for powerband, 34mm works fine. I have had MUCH better results using a modified stock 28mm carb body. The overall power is down only slightly with a much greater low/mid range power: A better overall choice for a balanced powerband.
I must add that I never developed my engines for maximum power as my home track was Sears Point, but my engines didn't suffer at anyone else’s hands at tracks like Willow Springs or Riverside either. I always believed that a balanced combination with smooth power was better than an engine that wouldn't pull its hat off its head below 8,000 only to wrench the wheel loose from the ground at 8,001 rpm's."

Cheers

5port
   
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