KTM EXC big bore 610

[Seekins]

Anyone running a 500 bumped to 610? How much HP gain?
Thinking this with Raze nitrous and ECU for next year but want to start riding bike this summer to make sure all bugs are worked out before snow flies. Just don't know how reliable the 610 kit is and if there's much of a improvement over stock. The nos will put me at 94hp with stock motor. ?????

 

[rhino89523]

I don't ride one, but ride with a guy who has that set up. The thing is a tractor and pulls like crazy. Seems like it is more of a torquer than something that winds up. It has been rock solid reliable. My 500 will pull it on hills if I am in the meat of the power, but he walks on me in the rare event we are on the flats...I think having the extra gear is what does it. He can just put it into a gear and leave it there and just roll. Seems like a great set up. He is not using it as a summer bike.

 

[eric82930]

Can you clarify what 500 can pull it? I'm assuming a 2 stroke.

 

[roo]

Anyone running a 500 bumped to 610? How much HP gain?
Thinking this with Raze nitrous and ECU for next year but want to start riding bike this summer to make sure all bugs are worked out before snow flies. Just don't know how reliable the 610 kit is and if there's much of a improvement over stock. The nos will put me at 94hp with stock motor. ?????

I am running a 2002 520 punched out to 570 with a hot cam.
It is an absolute beast compared to stock. 50 mph on pavement drop it down to 4th, wick it open and it stands right up on the back tire without pulling back on bars. With the hot cam it runs like an sx 450, revs super super fast!!!!! Nothing beats doing wheelies by other bikes climbing a dune! Has not been touched other than adjusting valves since built and stiill runs flawless. Very reliable! I had BREWSTER WEST out of alberta build the motor.
Cant speak for the 610 but if you get ahold of these guys they will definatly give you the lowdown on the 610 reliability and a good bore/cam etc. Combo
Good luck

 

[rhino89523]

Yes CR500, not me who is saying it...he says mine runs away on climbs. I can't really tell that much, I just notice as we are running through the woods when I am behind him it sounds like he is using one gear to my 3. I like it and would do a 610 in a minute if I wasn't happy running my 500.

 

[Dam Dave]

Wide ratio transmission will still be a handicap, I will never do a snow bike with WR trans again

 

[Butta]

Wide ratio transmission will still be a handicap, I will never do a snow bike with WR trans again

Please elaborate on why. I'm going to build a snow bike for next winter and am looking at a '17 CRF 450RX (close ratio) and a YZ450FX (wide ratio). The FX's seem to be really popular snow builds, but if the close ratio trans would be beneficial then the RX seems like the perfect machine.....?

 

[rhino89523]

I agree on the wide ratio thing but I'm a 2stroker. I might pull the motor out of my sand cr with the close ratio tranny and run it in my snow bike. When I get up on the pipe in third on some climbs I am so close to pulling 4th but that's where the gap starts on the later model cr500's. If I was close all the way through lapping gear to gear the thing would be perfect. Yes I will get spanked harder by a 6 speed running across a flat lake or something...but I dont care about being the king of the flats.

 

[Seekins]

I found the specs on transmission gearing.
Exc 500 vs 450sx.
500's 2nd is sooo close To SX 1st
3rd is super close to the SX 2nd
4th is dang near SX 3rd slightly taller.

I would like to have a 6th gear for the trails and in big open flat spaces. Right now I'm running a 14 front sprocket and I'm wound tight in 5th. I read that you can put a 6th gear in a SX so I'm going to do that instead. Love that way this SX rev's and it's more my riding style. some nos and it will be awesome.

 

[Timberview01]

I am running a WR 450 with a 120 Moto Trax. My riding partners are on RMZ 450's with TS kits. There is definitely a difference in gearing between those set ups. In first, I can walk next to my bike at an idle (which has come in handy in some of the hell holes we have found ourselves in) and most climbs I will be in 3rd where they are in 2nd. When getting a run at a hill, I will hit 4th and then downshift whereas those guys just pin it in 3rd and try and hold it.

In my opinion, the WR transmission is not a hindrance. I bought this bike for year-round use, so it was the best overall choice for me. I had a YZ 450 prior, and did a lot of gearing and Rekluse to make it trail friendly. The WR bone stock is an awesome trail bike. I was going to hold out for the FX, but found a screaming deal on the WR. The biggest detriment between my set up and my partners is the track. There is no arguing that I will spin out and get stuck while the TS will keep motoring.

 

[Colo moto]

A buddy of mine runs an early 2000's KTM SMR 560 bored and stroked to 610. As far as engine goes it has been very reliable. He's running it on a TS 137 and it has no problem going anywhere. I would say do it.