TRX cyclinder on ATC?

[Lomax]

In all the 250R stuff that I picked up there is an LRD ported cyclinder for a later model TRX, like an 88-89 I think. Anyway, It uses an intake bridge where the 86 (ATC) cyclinder does not. The sleeve skirt is a little shorter where it goes into the block but the cyclinder body itself looks to be the same hieght. I was wondering if this setup would work on my R? I know that the bridge in the intake helps with skirt cracking problems (I have already broke one). Anyone ever done this? is it a bolt on swap or is there some machineing that needs to be done?
-Will

[X2guy]

It will work

[X2guy]

I also beleive the bridge was added to reduce ring wear by supporting the ring as it passes by the intake port.
All year cylinders are interchangable. In 87-89 honda used a 5mm longer rod and to compensate they raised the piston pin in the piston 5mm.
Keep the Short rod (85-86) and long rod (87-89) piston and crank combinations together. The only exception is to run a 86 piston on a long rod and use a spacer plate under the cylinder.

[Lomax]

So the later cyclinder on the older (86) engine is ok with the 86 piston then right?

[jason85atc250r]

it will work if you use that newer 89 cylinder and use you 85-86 piston that matches the crank. actually a stock newer cylinder will make the bike run better then a stock old style one.