My friend just built a laeger crf450 quad.We are having problems with the chain getting loose and coming off when the suspension moves up and down while riding.also we are having a hard time finding the right gear ratio for the dunes.I really need to talk to someone who has built one and has maybe dealt with these issues already.I would love to see some pictures.I also wanted to know what we should expect out of this thing.I will admit my yfz450 runs very well with all the bolt ons and the cam mod.should i be beating him by 4 or 5 bikes up comp at dumont.we are both very skilled riders,he is also lighter than me by about 30lbs.that is why i think it isnt geared right or?i dont know but we need some advice.the next step is putting the 330 motor back in that and the 450 back in the bike and selling both.we are getting into this quad deep and either need to fix it or trash the whole project[img]i/expressions/face-icon-small-disgusted.gif[/img]any help would be nice.experienced help is prefered,this is a 15k dollar longtravel laeger.

 

I haven't built one but, 2 friends have. One was a crf 450, the other a yz426. They can't get them to run the way they want. The bike engines don't have the grunt for the extra 100 pounds of the quad frame. The crf450 has already been parked for a factory 450r.

I know this doesn't answer your question, but I think this is a commom problem with the power delivery.

 

I've never built that particular setup but have thrown many bike motors in trike and quad frames before the 300ex was ever introduced.

Besides the obvious problem of a chain being too loose the only other reason for the chain to pop is a misaliagnment problem. The easiest way to cure this is to use any type of laser level. Hold it flush against the rear sprocket(with the chain removed). measure the distance from the rear sprocket to the center of the laser. Make a cardboard, wood, metal target with a straight edge. Hold that flush to the front sprocket. measure from the front sprocket to where the laser hits the target (center of laser beam). do this in a few different swing arm orentations. if you are off by more than 1mm this should be your problem.

 

A CRF450 dirt bike motor will spank the YFZ! I have 2 hybrid CRF450 quads, both with PRP frames and they are awesome. The only reason to throw chains is a mis alignment issue or the chain is way too slack. I'm assuming you know how to properly adjust the tension on the chain?? Are you using a chain guide, if not, that is your issue or your 2 sprockets are not lined up. If that is the case you need to resolve that issue first. Gearing is easy, use a 14/38 and leave it alone, great for the dunes and great for MX.

Now keep in mind Laeger only built 6 CRF quads frames, so you are saying your buddy has one of these 6? I never liked that narrow setup Laeger did with those but they do handle well. Johnny Hale currently has one of those 6 Laeger frames. Call him at 918-371-0101 and ask him questions about it. I know he never had any issues with chains coming off and i know he always used 14/38 gearing as well.