500 Two-Stroke Tech

Message

bobbyd · #1 Post by **bobbyd** » Sun Jul 01, 2012 2:14 am

jackson.40 · #2 Post by **jackson.40** » Sun Jul 01, 2012 3:52 am

Hi Alex,

The RZ250/RZ350 powervalves are different.You can only use the 500 powervalves which are no longer available from Yamaha.

A while back Steve Rothwell was thinking of making them but it came to nothing.(see link)

http://www.rzrd500.com/500phpBB3/viewto ... ght=#49966

I have been in contact with someone in the UK who has was thinking of making some.I will find out if this is still the case.

Steve

bobbyd · #3 Post by **bobbyd** » Sun Jul 01, 2012 5:40 am

aaronmvrider · #4 Post by **aaronmvrider** » Sun Jul 01, 2012 5:48 am

whats wrong with your originals... where are they damaged

bobbyd · #5 Post by **bobbyd** » Sun Jul 01, 2012 7:02 am

bungerlowbill · #6 Post by **bungerlowbill** » Sun Jul 01, 2012 6:12 pm

a while ago i posted about wanting diamensions of powervalve tumbler including rake and valve angle of exhaust aperture but no answer, what i would suggest is making a sleeve for the bearing surfaces as this is the point of failure, i was thinking of making some sleeves up and turning down worn valve bearing surface down, fitting new sleeve to restore valve bearing size ,any help will greatly received as i have a lathe/milling machine so a possible service could be of use to us 500 owners as this was the idea i had in mind anyway, the seed has been sown lets see what grows regards to you all ,why be a mason when 500 ownership is of a higher order bill

aaronmvrider · #7 Post by **aaronmvrider** » Mon Jul 02, 2012 4:18 am

stator wiring... what part you needa photo of ...

i havent looked at the bike for a few weeks.... busy and its winter....

bobbyd · #8 Post by **bobbyd** » Mon Jul 02, 2012 6:31 am

bobbyd · #9 Post by **bobbyd** » Mon Jul 02, 2012 6:33 am

bungerlowbill · #10 Post by **bungerlowbill** » Mon Jul 02, 2012 5:05 pm

hi again, yes there is no bearing but valve has o'ring seal and sits in end caps so depending on whats wears i'e the caps or the valve tumbler this could be sleeved to take up tolerance of the excessive wear anyway hope this makes this clearer regards to one and all bill