250r vs 450r engine weight?

[bsmith106]

Whats up guys? First post. Just wanted to know if someone can tell me the weights of these two motors. I have a project in mind of installing the 250 motor in the 450 frame and was curious if there would be much if any weight lost over the stock 450. Thanks in advance for any help.

[chillinsk8err]

the 250r motor is alot lighter but idk how much they both weigth

[deathman53]

250r and crf/trx 450r motors are the same weight, about 60 pounds.

[Kirt13]

Originally posted by deathman53
250r and crf/trx 450r motors are the same weight, about 60 pounds.
Wow, I didn't know that. I would think that the 4 stroke would weigh a lot more than the 2 stroke.
Well, you learn something new every day.

[iamjasyn]

Well, that's not precisely correct... The R motor is I think 52 or 53 lbs. I'll look it up in the service manual later and edit the post. Anyone have the dry weight of the 450 motor? It should be at least a little less. The head is just a single turned piece of aluminum... I know overall the 450 has about 20lbs over the original R.

[deathman53]

the weight savings in with the nickel-sil lined cylinder, lighter alloy weight cases, lighter weight transmittion parts, etc. But, the major difference is that with a 250r the weight is lower, making the bike seam lighter, even thought its really not a lgither motor, they are around the same weigh, but with a 4 stroke, the weight is up higher, making it seam heavier.

[bsmith106]

Thanks for all the replys. I have an issue of dirt rider magazine that has the weights of various bikes disassembled and it lists the crf450s engine as weighing 64lbs. It also said that a kx250 engine was 55lbs. I dont know if there is a similar difference with the quads. I would just like a lightweight quad with two stroke power and as many oem parts as possible. The parts are normaly cheap and as close as your local dealer. That way I dont have to cry every time break it lol.

[iamjasyn]

Originally posted by bsmith106
Thanks for all the replys. I have an issue of dirt rider magazine that has the weights of various bikes disassembled and it lists the crf450s engine as weighing 64lbs. It also said that a kx250 engine was 55lbs. I dont know if there is a similar difference with the quads. I would just like a lightweight quad with two stroke power and as many oem parts as possible. The parts are normaly cheap and as close as your local dealer. That way I dont have to cry every time break it lol.

If you like 2stroke power, then put a 2stroke in it! The extra maintenance trouble and cost are the biggest problems with liking the recent 4stroke applications. Remember 2strokes have not been replaced by the bigger 4's because 4strokes are a better application for small engines. People like the newest 2stroke replacement and if you're not one of them, like me, then for god's sake run far away from that 450.

By the way the dry weight of the 250R motor is 57.3 lbs. If a 450 motor weights about 7lbs more, that means that there is a few pounds extra in the 450 chassis than the 250 chassis as well.