Noob question about bike vs quad engines

[idahoaj1]

so, ive been reading for a few days....
i still don't understand what the main differences between RM engines and LT engines are in the early years (85, 86)?
are bike engines interchangeable here where they didn't have the balance countershaft?
any input would be greatly appreciated!

[lt250racer]

The early lt250r's 85-86 engines are based on a enduro bike that is called a TS250x, This bike was only sold overseas, but its the same exact engine only with a Reed cage instead of a reed induction (piston port induction).
The RM engines are quite a bit different.

[idahoaj1]

how interchangeable in the chassis are the RM engines?

[NELSON]

I duuno for sure bout the rm engine but the 85-86 exaust comes out the side of the head. i think most bikes have a top mount also. u would also have to change the harness and electronics. best bet is to find something beat to hell like an old cr500 and drop in. i dont think u will find an engine that will drop right in. unless you go with a 87-up lt engine but even then u will have to fab the front bar into a wish bone.but all is possible. before decideing i would consider the rebuild cost, availibility, and power of the engine u choose

[idahoaj1]

i'm not too concerned about minor mount modifications, I used to build roll cages for a living.. I odn't minor fabwork to get it to fit, mainly i'm more concerned with vibration issues.

[Daveed]

I've seen alot of conversions using yz490, cr500, etc. They vibrate like you've lost your counterbalancer! The other option is the sportbike motors but they just are REALLY HEAVY and completely change your bike to a point and shoot only type of ride. No jumps or spinouts or carving a dune anymore but you'll haul arse in a straight line!

If you want to swap in a big bore motor put in a quadzilla motor. Just do the required mods to it first so it is reliable. Theres alot of info on how to do it on this site and another one called dr.quadracer? or sumpin like that.

[idahoaj1]

how is the vibration compared to the engine thats in it? I don't believe the early ones HAD the counter balancers, did they?

[lt250racer]

All lt250r & lt500r engines have counter balancers.
The site about the converions to lt500r engines is :Quadracerhq

[bmaccr]

just a question what are the differences between piston port induction and a reed cage? i think my cr has piston port inducion but what does the reed cage one do?

[idahoaj1]

thanks lt250racer for the info, I appreciate it