500 RD engine with 3MA barrels

Message

solex27 · #1 Post by **solex27** » Fri Apr 04, 2008 8:57 am

Hi,

I have the idea to put 4 TZR 250 3MA barrels on my 2nd engine.
I think it's not so difficult to fit 3MA on the case, the gudgeons holes are easy to mod (similar to TZR 400 mod).
I need to weld a torque box for reeds on two 3MA barrels for upper cylinders. No easier but possible.
But I have one main problem. I don't know the distance between head and base gasket plans on 3MA barrels to know if I could keep original rods or if I need to switch to other rods (as 125/250 TZR).

Anybody know this distance?

Cheers

Franck

#2 Post by **smurph** » Fri Apr 04, 2008 12:21 pm

The 3MA cylinders are the same height as the RZ cylinders. 90mm, if I remember correctly. I'm planning to use a 10mm spacer plate and RZ350 rods (110mm).

Actually, I will be cutting the deck of the case down 15mm and using a welded on 25mm spacer for a total of 10mm increased deck height. The spacer will become "wet" so that I can use the 3MA style cooling from the bottom of the cylinder. This extra 10mm will help in fitting case induction for the upper cylinders as well.

Steve

84rzv500r · #3 Post by **84rzv500r** » Fri Oct 17, 2008 1:40 am

howsabout 4DP

#4 Post by **smurph** » Fri Oct 17, 2008 2:08 am

Mark,

How's the Corvette coming along?

Yeah, 4DP would be nice. Just a bigger spacer. Their power valves may interfere less than the 3MA's. But what about the stroke difference? Aren't they 50.7mm?

Steve

gus · #5 Post by **gus** » Fri Oct 17, 2008 11:40 am

Smurph, when I had the cranks done I had them send me 10 sets with 110 rods on them, Mark got a couple but I have a few sets left if you need some

vma500 · #6 Post by **vma500** » Sat Oct 18, 2008 2:06 pm

Steve

3MA -3XV = 56 X 50,7mm
2MA- 2XT = 56,45 X 50

mbsteve · #7 Post by **mbsteve** » Mon Oct 20, 2008 4:11 pm

84rzv500r wrote:howsabout 4DP

How are you planing to supply water to the 4DP cylinders?

Jordi YZR500 · #8 Post by **Jordi YZR500** » Mon Oct 20, 2008 8:03 pm

This may help:

http://www.rzrd500.com/500phpBB3/viewto ... l&start=15

http://www.rzrd500.com/500phpBB3/viewto ... ght=barrel

http://www.rzrd500.com/500phpBB3/viewto ... el&start=0

http://www.rzrd500.com/500phpBB3/viewto ... ght=#32898

84rzv500r · #9 Post by **84rzv500r** » Fri Nov 07, 2008 10:08 am

mbsteve wrote:
84rzv500r wrote:howsabout 4DP
How are you planing to supply water to the 4DP cylinders?

Through the upper case half.... water enters the case flows to the cylinder under the exhaust port and goes out the top...

geosot · #10 Post by **geosot** » Sun Nov 09, 2008 9:05 am

And how you will supply fuel? You will modify the upper case to take reeds in the Vee ?