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How to tame my torquemonster?


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I have had my 2000 BRP for a few months now but just stumbled onto TT a few days ago. I am one of many who love the power of the beast, but I can't say the same about the bottom end- it just hits too hard for me. It was fun for about the first hour of the first ride in the tight woods, but then just became a pain. The immediate hit forward, accompanied by over the bars decelleration has never failed to take me off my lines, and fighting her sure is tiring; I'm a little guy, 160 lbs. In addition to woods and sand, I will be plating her, and I can't imagine riding this crazy torque monster on the street. I have owned a few liter-class sportbikes over the years, and I would like to have her run more like that: the slow, lazy grunt up until about 4k and then all hell breaking loose. I haven't seen anything on this board on this subject, so I thought maybe someone can make a suggestion on cams, pipes, or the like.

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the only thing I can think of to change the torque is to change the cam and/or the pipe to shift your power range towards the top end.

i'm currently looking at either the HotCams Stage 1 (similar to the HRC) or possibly the Stage 2 if I change the cam, otherwise I might wind up just waiting and doing the full blown 680 with barnum pro cam.

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Haven't heard much about detuning the R motor. Before doing any motor work, try going 1 tooth larger on the cs sprocket or down 3 teeth on the rear, or both. This will also help the top end for the street once it's plated. I used 15-47 on my WRF and it toned it down quite a bit from 14-50. Just a thought. :D

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Gearing is now 15-43, which helped a lot as I couldn't get into 2nd gear in the tight stuff anyway. Still cranks the wheel up from just off idle in the first three gears! I'm really not talking about detuning here, but raising the power band. Preferably gaining the torque I'll lose down low to the hp up top and then some. After doing some looking, seems like I need a cam change, as the factory pipe is fully uncorked and apparently flows almost the same as the aftermarked stuff. Anyone have a cam they like for this application, keeping the factory compression ratio?

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Are we talking a 650R or L? Either one are heavy thumpers and a handful in the woods or any technical section. Going down a tooth on the CS sprocket and not twisting the throttle so far will help. This aint no two stroke we are talking about. The XR400 (as mentioned by Max Power) is a better woods bike.

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Tame ? what is/does that mean I am always trying for more power.

I think I am related to Tim the tool Man!

MORE POWER!

Really if you are smart cause you must be owning liter street bikes ( I have had my share) I think you will get used to it and the power will become your friend. Just like the power of an R1 can get you out of situations so can the power of the 650 pull you through. Patience with the throttle

Travis

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If your going to ride on the street the taller gearing is a plus anyhow, I run 15/45 and it's a blast on the street about 1/3 throttle at 75 mph and much better fuel economy, I may go to 15/43 even, but I want to give it a full riding season with 15/45, you could try a CV (constant velocity) carb off a 650L that should make it more user friendly and better fuel economy, maybe one on Ebay or someone parting out.

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Yeah the 650R uncorked and jetted is very 'trigger happy'. It's fun though. You will get used to it, just keep riding it and soon you'll get a feel for the touchy throttle response. Be glad that you only weigh 160, you're not slowing the bike down any, that's good. The 650R is all about huge torque, right now!

There is no way the 650R is going to run or feel like the power of a liter bike, since the liter bikes are four-cylinders and are very smooth and of course a lot more powerful. Big singles like the 650R are always very abrupt with their power (or should be anyway)

I have a Bandit 1200 that is at least twice as powerful as any XR650R, but it's so smooth you can ride it slow in town and it's not touchy on the gas, but when the road opens up, you get past 4 grand, twist it, and you get some very serious thrust that goes for a very long rpm range to 11 grand. No 650R can be made to feel like that.

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Go to a CV carb, which will eliminate the pumper hit. If the torque is still too much for your liking, smaller c/s sprocket, larger rear sprocket. If you do woods riding alot, and want it plated, think about a DRZ400S. Comes with a CV carb, smaller frame, but a little heavier than the pig. Use the pig for the open stuff, the DRZ for woods. The CRF/X bikes are wrench intensive and hard/impossible to plate in some states.

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The torque of that motor is considered a virtue of that bike by most! It's probably the strongest bottom end in the dirt-bike world. If you came off of a CR125 before it though it will take some getting used to! It's an awesome machine but hardly a small guys bike to be frank. Taller gearing will smooth out the hit, but ad a fair bit of clutch work in the tighter going. You might have been happier with an XR250 or 400. :D

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Thanks for the responses all! There is absolulely no way I will sell the Pig, however! I have ridden the XR400 and Yama WR's as well as the CRFs in both sizes (lots of riding buddies). I have had a few of both 500 and 250 two strokes and liked the power but not the flexibility. I have found all to be 'niche bikes' that can't do it all the way the BRP can; I'm just looking to set it up to my liking. I have a CR125 for the tight stuff and track use, but I would like the BRP set up to do it all as well as possible. I believe that this bike has the flexibility to be set up to my liking for almost anything, and that is the goal here. I really like the idea of the multi-rate throttle assy, that may be just the ticket. 650L Dave, got any more info on where to look at one? I have been looking at the Quicksilver to help out with the herky-jerky stalling problem in the tight stuff, but it probably would make the bottom hit even harder. The 600R cv carb may be just the ticket, anyone put one of these on the 650R? Keep in mind, this is just a brain exercise at this point, I am pretty happy with the BRP already.

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ALL RIGHT DAVE! TCS shows a nice pic of the cams and explains how they affect throttle application. I will pull apart the factory throttle and see if I can duplicate the 'flat spot' the least agressive ratio has. Mucho appreciated, it's a great first step!

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Another option is switching exhausts. Any larger diameter headpipe tends to really reduce the bottom end hit on the bike. An Edelbrock, 15/47 gearing and a Barnums or Moriwaki exhaust created a real smooth powerband that would only lift the front end if you worked some magic with the clutch, but still had excellent throttle response.

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