I'm looking into purchasing an 87 250R for real cheap, but the engine is blown. The guy said that the bottom casing would have to be fixed or replaced. He wasn't sure though. I was reading about the CT330 kits and saw that they cases are machined for those kits. Does this mean that it would solve the problem of the bottom end casing? Also, are there any other 330R kit's out there that are better than the CT one?

 

First, we need to know why does the case need to be replaced? Where is the damage on the case or cases?

Yes, CURTIS SPARKS, and LRD both make awsome 330 kits.

I used to have an "R" with a CT 310 kit. I liked it, but sold it to go back with my LRD motor. I since have sold my bike all together, and went with a 400ex.

 

I'm not exactly sure what is wrong with the cases. I've only talked to the guy on the phone, and not yet seen it. I was hoping for the chasis to be in a good shape, and fix up the motor back to stock condition if possible. If that wouldn't work i was going to find a replacement motor i could bolt into the chasis. Hopefully though, if the motor can be fixed for not too much money, i would love to have the 330R kit. The only thing is, i don't race, i'm just a weekend warrior. Sometimes only once a month. So i need to know how reliable the 330 kits are. Will my quad always be there for me when i want to ride? How often am i gonna have to rebuild the engine with the kit? and is it gonna cost more than a stock rebuild? The main thing i want though is reliability.

 

Sure, the big-bore can be very reliable, but they don't come cheap.
If you want inexpensive reliability, keep the motor stock inside and add a few mods to the outside (pipe/silencer, reeds, air-filter/air-box). It will produce enough power to give a great ride for a long time.
How often will you need to do a "rebuild" (I think you mean a top-end)? I dunno. Impossible to say. Depends on too many factors. I have a friend that has an all-original 88 running still! How's that for dependability/durability?

 

There's PLENTY of power in the stock cylinder! A good port job from a quality shop give you as much if not more power than these (CT) big-bore kits,and cost a lot less. Of course the better shops can make awesome Big bores but unless all you do is drag race a 70+hp motor is not what you want.

Modifying cases for a bigger sleeve wont fix any damage done by blown tranny or crank. I wouldn't buy it until I saw exactly what is wrong. Cases,crank rebuilds and trans parts are not cheap!!

If you keep dirt out of the motor(clean air filter every ride)and jet it right a 2 stroke will last as long as any 4 stroke.

 

I'm with Chris...I have a stock jugged R, and its the fastest stock or aftermarket jugged R I've ever ridden, it was built by MP Racing in Salem Oregon

 

When you say stock jugged, you mean stock bore, but with a port and polish job? If the motor is in bad shape, and i do half to replace it, how much should i expect to pay for just a trx250R motor? not one of the old atc's. And what other engines could i bolt in that would give me the same power, but not stress and crack the frame?