Hi all, I have a 1992 3TJ Deltabox frame and was wondering what size engines would fit without much in the way of modification?? any help would be great

600cc yamaha thundercat/600cc foxeye engine goes in relatively easily. check out the other threads on here for whats involved.

ThunderCat or FZR600R Foxeye are probably the best ones to use. There are a couple of threads on here with people doing the conversion.
These are good as the bottom end is the same as the 400 engine so the front sproket will line up with the rear no problems.

With a bit of mild tunning you could see 100bhp.

evil - how much modding do ya rekon it would take to get that blade engine in like the one that was in the bay???

Enough !!!

The bottom end almost lines up ... I think the front sproket is spaced.
The TJ top mounts are cut and rewelded .... that's the engine in. Now you need to mod the pipes to the can and try to keep the designed length from the Blade if you want it to scoure the gas to optimum. I tink they had a new loom made but remember it had lots of different bits on top of everything else so unless you know the bike it could be difficult to trace a problem.
I think it was the original engine used ie 918cc

On the old forum somebody heavily modded a T'cat engine and got 720cc from it big bore and stroked the crank etc ... cost about £3K for the engine work. He said it absolutely flew !!!

ummm stroking cranks aye

sounds like lots of work and money which can be better spent in the pub !!!!!

Possibly - I saw Fifth Gear where they did a study of the average amount of money spent on booze for a year ... they then took out a loan for the monthly amout and bought a car... I think it was £1500.

hmmm hows bout a 600 conversion get it tweaked slightly and bolt a low compression turbo on or even happy gas ??