Hi All, Chasing a FZR250R 3LN1 - 3LN3 engine to replace the track bike engine. Require head, barrels and bottom end. Everything else will come from the track bike. Australia only please. Queensland would be great. Prepared to buy complete bike at right price.
Out of interest, what went wrong? I know both @gregt and @Mike Green have some advanced insights on preparing the cranks in their various threads
I have a Zeal that you can have.... all you would need to do is pay for the transport from Sydney.....not sure how the engines differ though. It does have 100,000 km on it though
Bottom end let go 'again'!! I will take a look at the threads you mention. I have also been told of some other 'tricks' to ensure better oil delivery.. Thanks @ruckusman.
Yes, I'm not certain where the information lives - @Mike Green also has a large thread on Kiwi bikers I think it is about his turbo half and I know both Mike and @gregt have discussed radiusing the oil feeds to the mains and big ends to improve flow - but I don't want to misquote them and steer you wrong There's a really serious depth of knowledge between those two Now one thing which I cannot find the original source for is putting a shim in the oil pressure bypass - it was related to FZR400's because the oil pressure bypass is very close to the oil pressure at high RPM Wow I just found it, I was searching for oil pressure bypass, the correct search term was oil pressure relief Mentions the oil pressure at peak RPM being close to the relief valve working pressure https://bdkraceeng.co.uk/tc/products.php?357&sid=5ekskbctc0oqduumtsep0unk66 Mention of using the shim in an FZR400 https://www.gtamotorcycle.com/xf/threads/fzr400-winter-overhaul.178050/page-4
i have a recently blown engine that i don't need, crank would need a linish on one journal, barrel is good, head has oil starved cam journals, cases are good.
I've come to the opinion that there's not too much wrong with the oil pressure in these engines. Where they and a lot of others too fall down is the finishing of the cranks. Production times don't permit inspection and rectification of poor oil hole finishing IMO. I now routinely radius the oil holes in all crank journals - mains and big ends. I doubt if it improves flow to any significant extent - but it avoids the shearing of the oil film which occurs when there is a sharp edge left on the hole. Shear the oil film and it results in metal to metal contact - and bang!
Just scored a pair of 3LN3 engines, 1 in bits & has no valves. Looks OK. Know anyone in Melb who'd check it out to see if any good to you?
