anyone try this?

[flat_track400ex]

has anyone put a crf250 motor in a 300ex frame or a 250x frame i'm looking to getmy fiance a crf70 for now but i'm looking to build her a quad and i was thinking about the crf250 motor but i wanna know if anyone else has tried this?

[flat_track400ex]

bump someone has to know something on this

[400exrider707]

why bother why dont you just buy a 300ex for her? It would probably be cheaper than the conversion. If you only wanted to get her a crf 70 then I think the power from a 300ex would be more than enough. Other than that if this is something you really want to do its just going to be a trial thing. You will have to make some parts yourself too. Its not a common swap at all, actually this is the first one I've heard of. The commong swap is a 350x motor into the 300ex frame. Lots of people do that but that would be cool to have the crf motor in the ex frame. Whats the power output on that motor? The problem is anything that puts out more power than a stock 300ex usually, the frame cant handle it. So you would have to do a-arms and swingarm to keep the front end down and probably gusset, and definitely shocks. Hope this helps some......

[flat_track400ex]

i just firgured this would have more power than a 300 would cuz she one of those girls who wants to go fast all the time and i was looking for a project for my self while she is in school i just diidnt know if anyone else has tried this

[300EX777]

I have actually heard of someone putting a YZF250 motor in a 300ex frame. They had to modify the frame a lot to get it to fit just right. Said the hardest thing was getting the angle of the motor right for the rear axle. Also said the pipe was easier than they thought. All in all it turned out to be pretty expensive, but worth the effort.

They use the machine to race in the sport class flat track/tt series. I believe the stock horse power with no motor work done on the YZF250 is 30-35.

Wish I could remember the website I found the project on. They could really give you some tips to make the transition easy.

Keep looking, your not the only one wanting to do it. Plus people on 400's will freak out when you fly right by'em.

[flat_track400ex]

i just talked to a place that sells motors and he said i was like 6th guy to call int he last 2 weeks asking about this he said that a guy did one and said he used a 400ex frame and it was relaly easy alot easier than the 300 frame.

i just got a 450r and i wanna build her somethign that will ask least beabole to stay w/ me when we go ride threw fields and weere ever else and plus i figured that would rip pretty good in that class and w/ her only being 115 pounds

[400exrider707]

If shes one of those chicks that likes to go fast then why a crf 70?

[flat_track400ex]

cuz i want the 70 for a pit bike and she will ride it