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Well I've had my '05 650R for about 5 months now, I've uncorked it and had it dyno tuned - got peak power of 42 hp which I don't think is bad.

This thing is so much fun it's insane - my other bikes 1150GSA & 950 Adv are now feeling very neglected!

As motorcyclists do, I got to thinking (always dangerous) how much more power would I get with a stage 1 hotcam and a 11:1 compression Wiseco (std bore)? Anyone done just these mods and what were your results? Does this sacrifice a lot on the reliability side?

Would adding an Edelbrock to this setup make a significant improvement in the performance department?

It's not that I need more power, ut rather I WANT more power. :thumbsup: Any advice / opinions would be greatly appreciated.

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What are the guys claiming 55 HP doing to their XR650s? 42 aint bad,but I was thinking more than that from what ive been reading on here.

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The 11:1 piston is right on the borderline for race fuel. My stock compression bike had some pinging with 87. Ive been running 93 in it and it makes all the diffornce. But idk that the bike would run ok with 11:1 on 93 octain. So make sure you take that into concern.

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I would go with an FCR carb, if you have patience with jetting. The most power with the most reliability too. Otherwise, Edlebrock. Either will dramatically improve throttle response and torque, starting, ease of riding, etc. HP will go up slightly with Edle, a bit more with FCR. After that, I'd do a cam.

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How much power will an FCR add? Any loss anywhere? What does one of those cost?

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I'm a bit confused here, what is the actual size of the standard Mikuni carb? The manual says a throttle bore of 42mm, on Borynack's dyno charts they talk of 40mm?

If I were to go for the FCR, would the 41 be the one to go for? I see a lot of them seem to have a throttle position sensor, if I pick up one of these is this a problem or can the TPS just be ignored?

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What are the guys claiming 55 HP doing to their XR650s? 42 aint bad,but I was thinking more than that from what ive been reading on here.

To get into the 52+ whhp you will need at least an HRC cam and 11:1 piston on the XR650R to get above 55rwhp it has to be 680cc, cam and 11:1 piston. Nicasil cylinder makes a big difference and I wouldn't build another without it. Pumper carburetor makes things nice. To get above 58rwhp I have a 42mm Edelbrock. There are a lot of dyno numbers out there that are bogus because they are componsated. Rear Wheel Horse power is 24% less then Breaking Horse power which is messured at the flywheel. These are the number that Honda uses so, 55bhp which is 44rwhp that you should get close to on the dyno. 58rwhp is 72bhp. Honda Teem #1 had 52rwhp but, if you read anything about that XR650R it was told to have 64hp and that would be Breaking Horsepower. So, it is nice to know what numbers are what? What? But, some dyno shops will have the number componsated to breaking horsepower.....those number are a joke.

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To get into the 52+ whhp you will need at least an HRC cam and 11:1 piston on the XR650R to get above 55rwhp it has to be 680cc, cam and 11:1 piston. Nicasil cylinder makes a big difference and I wouldn't build another without it. Pumper carburetor makes things nice. To get above 58rwhp I have a 42mm Edelbrock. There are a lot of dyno numbers out there that are bogus because they are componsated. Rear Wheel Horse power is 24% less then Breaking Horse power which is messured at the flywheel. These are the number that Honda uses so, 55bhp which is 44rwhp that you should get close to on the dyno. 58rwhp is 72bhp. Honda Teem #1 had 52rwhp but, if you read anything about that XR650R it was told to have 64hp and that would be Breaking Horsepower. So, it is nice to know what numbers are what? What? But, some dyno shops will have the number componsated to breaking horsepower.....those number are a joke.

True. You cant ride the pig without a trans, and drivetrain...

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So, I am an extreme newbie -- not just to the thumpertalk world, but also to motorcycles in general. I purchased an XR650L about 5 months ago or so and learned to ride on it. I have about 6-700 miles of experience and as of right now, use it to commute around town for the most part, with asperations to take it off road more and more as my riding skills improve. I took a look at what you all had to say on this particular subject because I feel I would really like a bit more torque, particularly for highway riding which I do quite a bit. Top ends on this bike are more than fine, but it doesn't react on the throttle as well as I would like. Some kind of power-up modification would be nice. Much of the industry specific language you use is a bit Greek to me, but I wondered if any of you more knowledgable folk could be of any help to me. Any sound advice would be appreciated and please excuse my ignorance.

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There's some evidence of what I was just talking about. Not sure why this posted twice. Sorry about that. I'll get it together.

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So, I am an extreme newbie -- not just to the thumpertalk world, but also to motorcycles in general. I purchased an XR650L about 5 months ago or so and learned to ride on it. I have about 6-700 miles of experience and as of right now, use it to commute around town for the most part, with asperations to take it off road more and more as my riding skills improve. I took a look at what you all had to say on this particular subject because I feel I would really like a bit more torque, particularly for highway riding which I do quite a bit. Top ends on this bike are more than fine, but it doesn't react on the throttle as well as I would like. Some kind of power-up modification would be nice. Much of the industry specific language you use is a bit Greek to me, but I wondered if any of you more knowledgable folk could be of any help to me. Any sound advice would be appreciated and please excuse my ignorance.

When you rejet the stock carb, Using Dave's Mod's... It will react MUCH better on the bottom end. It will also start cold so much easier. The next step up from that is a pumper carb. A carb with an accelerator pump. With each twist of the throttle, you get a squirt of fuel that pretty much overrides the classic "cough and die syndrome". That's when you whack the throttle and the engine coughs and dies, or hesitates.

You are not ignorant, just new!:thumbsup:

Feel free to ask any and all questions.

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When you rejet the stock carb, Using Dave's Mod's... It will react MUCH better on the bottom end. It will also start cold so much easier. The next step up from that is a pumper carb. A carb with an accelerator pump. With each twist of the throttle, you get a squirt of fuel that pretty much overrides the classic "cough and die syndrome". That's when you whack the throttle and the engine coughs and dies, or hesitates.

You are not ignorant, just new!:ride:

Feel free to ask any and all questions.

http://www.4strokes.com/tech/honda/xr650lcarbmods/ ;):p

and a bunch of other gud stuff here... http://www.4strokes.com/tech/honda/

and don't forget the FAQ's sticky at the top of the page...read & learn wuts there and ur noob status will quickly be removed :mad:

:rant:

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