Wilsons Sandbox

Rob (prisoner6@...) wrote: [engine mods] It's not just crank mass, there is rotating mass in the counterbalance system as well.

> Now i'm considering more serious options. Big bore maybe? I don't > really want to push the motor past its limit though...i'm aiming at > 65hp, is this too high?

IMO, yes, too high. The KLR is an old design based on the 564cc KLR600 of 1984. You are expecting a ~50% increase from a normally aspirated motor which is already DOHC and 4-valve. If you have enough money to make a KLR put out ~60hp then you have enough to buy a new XR650 which makes similar power out of the crate. Mister_T Melbourne Australia

Mike wrote:

> I think if you port and polish, mill the head bump compression a little, > Install a 38mm flatslide carb, You would see a major increase in power. and > not hurt the life of the motor, But i could be wrong, Now with 38 stock HP , > A major increase would be maybe 10 to 12 HP,

I'd be wary of skimming the head or block to get more compression since this will retard the cam timing and reduce the effective amount of cam tensioner travel available. Once I start thinking of ways around this, it all gets too expensive if I expect to pay a workshop to do it for me. No doubt that work on the ports would be beneficial. I don't think there is much that can be done to the chamber itself, it is already reasonably full of valves and has a fair amount of squish area. Too bad the angle between the intake and exhaust valves makes adding lift, dwell and duration to the valve timing a bit tricky. I guess it may be simpler to bodge a XR650 engine into a KLR frame. Mister_T

Mike, Ted- I think the only viable option for getting seriously more power would be Quality R+D's overbore operation (upto 770cc I think). They claim 70hp and 60 ft-lbs torque from their 770 overbore. The problem is that I can't imagine it being cheap, in fact, I bet the work would cost more than a new bike itself, and they don't do it (i.e. they did it simply to do it, but they have no plans as to actually do for anyone else). http://www.qualityengine-rd.com/action.html has pictures of their Ninja 770. I think it was Jim Jackson who has been to their shop and worked with them on their KLR muffler. here's the reply from Steve(?) Kess: Hi I`m sorry it took so long to get back , but here`s why . What we do here is do research and development for other companies , and our own , as well as manufacturing . We are trying to get the manufacturing started on the other lines of mufflers , ( the Harley line is already started ). As well as getting a few other product lines started . We don`t do any work for the public at this time at all , heck , I don`t have time to work on my own stuff. Well any way , our web site does show some of what we do here , and what I`ve done in the past , so companies will have an idea of our capabilities , and so the public can see that anything we design and manufacture is going to be top notch " stuff " only . because of my lack of time to sit and return e-mail questions , it`s easier for me to just take a quick call and answer a few questions . If ya give me a quick buzz I`ll be happy to give you any advice I can , to help you achieve your goal, without wasting time or money , and any other questions you might have . our web address is qualityengine-rd.com Thanks S Kess ------------------ Zack SE DC KLR650A5 "Buster" ZG1000A1 COG #4664 -----Original Message----- From: Ted Palmer [mailto:tedp@...] Sent: Wednesday, April 18, 2001 10:01 AM To: DSN_klr650@yahoogroups.com Subject: Re: [DSN_klr650] crank mass Mike wrote:

> I think if you port and polish, mill the head bump compression a

little,

> Install a 38mm flatslide carb, You would see a major increase in

power. and

> not hurt the life of the motor, But i could be wrong, Now with 38

stock HP ,

> A major increase would be maybe 10 to 12 HP,

I'd be wary of skimming the head or block to get more compression since this will retard the cam timing and reduce the effective amount of cam tensioner travel available. Once I start thinking of ways around this, it all gets too expensive if I expect to pay a workshop to do it for me. No doubt that work on the ports would be beneficial. I don't think there is much that can be done to the chamber itself, it is already reasonably full of valves and has a fair amount of squish area. Too bad the angle between the intake and exhaust valves makes adding lift, dwell and duration to the valve timing a bit tricky. I guess it may be simpler to bodge a XR650 engine into a KLR frame. Mister_T Visit the KLR650 archives at http://www.listquest.com/lq/search.html?ln=klr650 Post message: DSN_klr650@yahoogroups.com Subscribe: DSN_klr650-subscribe@yahoogroups.com Unsubscribe: DSN_klr650-unsubscribe@yahoogroups.com List owner: DSN_klr650-owner@yahoogroups.com Support Dual Sport News by subscribing at: http://www.dualsportnews.com Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/

--- In DSN_klr650@y..., snomobill@y... wrote:

>We radared some different friends klrs, 600's and 650's >with stock to bolt-on mods. All ran within 1-2mph of 90mph actual, >even the 600.

I don't feel so bad now. I had two opportunities to top-end my bone stock A14 (except for a 16T sprocket) last weekend. I could never get the bike over 100-102 indicated. Given the 10% speedo error, 90- 92mph sounds right. RM

The 16t bike in our group went faster in 4th gear, did yours pull 5th? have you tried the 140 DJ main? my experience showed it to top end as well as the 150 with bolt-on mods. At topspeed you can roll out of the 150 a tad and not lose anything, tells you its a bit rich. Best mod I did to my bike was removing the handguards (warmer glove may be needed) and narrowing the bars as much as the controls allowed. This almost eliminates the jet-wash wobble you get from the cars, much more than a low fender (I put the stock fender back on and couldn't notice much difference). So tell us about your custom exhaust? I use the "wileyE mod" as some of my riding has me trespassing and riding around closed gates. The loud silencer goes on when I ride a couple local tavern runs with the harley guys. Got a drilled and gutted cobra with the angled outlet aimed right at the half-helmeted hogsters, he-he. cheers

> MY Y2K will show 110 to 115 MPH with 16 T front, K&N filter

Dyno jet kit

> 150 main, Coustom pipe.

Zachariah Mully wrote:

> I think the only viable option for getting seriously more power would > be Quality R+D's overbore operation (upto 770cc I think). They claim > 70hp and 60 ft-lbs torque from their 770 overbore.

Yup, and even then I would hazard a guess that after whatever mods were done on the head they still wanted more flow through it. There are always alternative powerplant options, like the engine from the Suzuki DR750BIG, even though I don't think they are particularly powerful stock. I've run my 600 against a DR750 some years ago and the 600 left it behind.

> The problem is that I > can't imagine it being cheap, in fact, I bet the work would cost more > than a new bike itself, and they don't do it (i.e. they did it simply to > do it, but they have no plans as to actually do for anyone else).

My point entirely. It would be a fun thing to do if I had all the experience and workshop facilities sitting idle. Just considering details like increased radiator area, crankcase breathing, recurved ignition advance, crank reliability etc etc, before worrying about bottom end reliability adds up to lots of dollars. Mister_T