rapido 225 with 116mm con rod

[dave wheeler]

Am currently running a fairly stock s3 TV175 but have aquired a 200 block with the intention of building a smooth, bulletproof, economical mile muncher. I am considering using a rapido 225 barrel with a 116mm rod and piston, is anyone running this setup and are there any technical problems running this set up in a barrel designed to work with 107mm con rods regarding the ports

[corrado]

I've got a few spare Indian 200 barrels so was looking at doing a similar conversion using the RB20 piston and 58 x 116 rod along with a scootrs reed valve. I hadn't envisaged any extra problems over what the long rod / piston already provide.

[lofty]

i am also considering this setup.. I have a rapido classic barrel already which should allow the porting to remain 'sensible' with the longer stroke/rod.. i am just debating over pistons and what are available in a lower compression height..
im thinking kawasaki h2 (71mm) or equivalent wiseco/wossner
devtour
mugello

also wondering whether to go reed valve or not..

so I am too interested in any experiences or thoughts or suggested parts..

[Spanish Fly]

If you go reed inlet you can go with the RB20 piston, as Corrado suggests. The RB20 piston is actually a Yamaha Blaster piston so oversized versions are available up from the stock 66mm.
SF

[lofty]

cool.. just looked, the standard 'blaster' is 66mm upwards, but theres an 'airsal' big bore kit with a 71mm piston for a 225 barrel, maybe that will work..

[fairspares]

my rapido barrelled sprinter uses the af rb crank with 116 rod but im using bultaco comp piston with barrel base machined to get the timings requirred. if you want have a word with Ben@af he has a few different options available.

[steveg]

Just about to pick up my newly built engine, top end spec-
Indian crank webs
116mm Yamaha conrod
Race spec Yamaha big end bearing
18mm small end
Yamaha DT 250 piston
AF re-profiled Head (yam spec)
Rapido Boost ported cylinder
Reed-valve
Also got 5 plate clutch set up, BGM full DC wassel conversion and Jockey rear brake
Looking forward to getting it up and running.

[wack 63]

Do you know what conrod was used, I thought Yams were all 16mm small ends?

[steveg]

Do you know what conrod was used, I thought Yams were all 16mm small ends?

Sorry Wack I don't, just quoting what I've been told

[wack 63]