www.zxrworld.co.uk

the sensible option is to buy a zxr400 engine so the bike is a runner. then strip down the zx4 engine and replace whatever needs replacing. its also a good opportunity to replace things like the main/big end shell bearings, get the piston crowns and conrods x-rayd for defects then get them weight matched and ballanced to the crankshaft...basically blueprint the bottom end...your engine will love you for it

banner001 wrote:the sensible option is to buy a zxr400 engine so the bike is a runner. then strip down the zx4 engine and replace whatever needs replacing. its also a good opportunity to replace things like the main/big end shell bearings, get the piston crowns and conrods x-rayd for defects then get them weight matched and ballanced to the crankshaft...basically blueprint the bottom end...your engine will love you for it

Basically, I'm doing that sans the ZXR engine. The fairings are buggered too, so it's turned into a full restoration project.

banner001 wrote: get the piston crowns and conrods x-rayd for defects then get them weight matched and ballanced to the crankshaft...basically blueprint the bottom end...your engine will love you for it

Is this something you have experience of ? if so could you recommend a company that could carry out this work and a current price ?

i was helping a friend to renovate his triumph 6t
http://www.coventrybikers.co.uk/phpBB2/ ... =60#p73876

he took the conrods here:
http://www.ndtservices.co.uk/

could have taken the pistons as well, but it was easier to just buy new along with new rings, although i have no idea of the x-ray cost, wont be a lot as they are only imaging it.
welds for nuclear subs go through the same inspection procedure to test integral strength.

Rodger do you have your pistons and conrods crack tested on yuor race engines also wood you now you no wear to get it done? also the cranksharft.

matthew wrote:Rodger do you have your pistons and conrods crack tested on yuor race engines also wood you now you no wear to get it done? also the cranksharft.

Would you like to try that again in English ?

Rodger do you have your pistons and conrods crack tested on your race engines? also would you now that you know where to get them done? and would you have the crankshaft balanced?

Ive been tuning and building race engines for the last 20+years and never had any failures in that department, So unless some people know something i dont...then i would suggest its a complete waste of money. I do use a metallurgical specialist from time to time 'Keighley Labs' mainly on the Weslake drag bike i work on. I do lighten crankshafts myself so it is necessary to have them balanced again, i use 'Engine Data Analysis' at Castleford. As for a standard engine... again a waste of time even taking it.