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View Full Version : xr600r or xr650r in a 400ex?


raciea
08-25-2010, 04:39 PM
i am new to the forum and getting ready to make a 600r or 650r / 400ex hybrid.Â_ i have been looking all over the net for info.Â_ what is everyones thoughts on which one to go with?Â_ flat track or "tt" racing is becoming popular here in the foothills of nc.Â_ based on the classes available i have decided to go with one of these big bore engines instead of trying to build up the 400.Â_ i have noticed that the horsepower between the two is pretty close with minor mods.Â_ mechanical ability and fabrication is not an issue but if the 600r would be a easier install, that may be the way i would go.Â_ i hear a lot that the 600r is pretty much bulletproof in stock form.Â_ the 650r may be also, i just do not know.Â_ any info much appreciated or if anyone knows of any good sites to look at.
tayyo789
09-09-2010, 04:49 PM
You aren't going to find a lot of info about them. It's not as popular of a build, since everyone that is building hybrids are mostly doing 450's and 250's. The 600 probably will be easier, but the 650r is a very strong motor. I don't know what classes there are for you to race in with a motor like that either
805ds
09-10-2010, 10:51 AM
I in particular recommend the XR 650,its about the same weight of the 400ex motor and its very reliable,Im in the process of doing my Roll Design lobo into one of these.
I found a guy whos has done it,I googled atv xr650 build and it came with pics an all.He did on a 250r frame.Also on the race dezert classifieds there was a guy from Arizona that had one for sale,his 400ex build was very nice,mostly a desert quad.:)
805ds
09-10-2010, 10:53 AM
Here are some pics!!!
805ds
09-10-2010, 10:53 AM
pic
805ds
09-10-2010, 10:54 AM
pic
tayyo789
09-10-2010, 02:47 PM
Of course, a custom frame is the way to go, and you actually won't spend much more doing it that way. However if you do wish to do a conversion, do the 650r, not the 650l, and ask questions on here. I don't have a build thread, but I built one myself, and there are a handful of others on here that have as well and we did a lot of things differently so you'll get different opinions on each obstacle when building it. It's a lot of work, but its worth it cuz these motors can run circles around the 450's in the right circumstances