lots more tire questions....

[bkowal@cgocable.net]

The stock KLR has a mild compression ratio of 9.5:1. Most other large "performance" singles (KTM and KLX) are in the 10.5 to 11.0 range. Boosting to 11.0:1 would give an easy 16% performance gain. I figure by running premium gas, the general robustness of the engine, the water cooling and by adjusting other tuning items (jetting and plug tempuratures) the reliablilty of the engine would not be reduced. The question is what is the most effective way to boost the compression. The easiest way would be to replace the stock piston with an aftermarket performance unit. I have been unable to find a high compression piston for the KLR. I have noticed that the KLX 650R has a 10.5:1 ratio. Maybe the piston would fit in the KLR to give it a boost. It seems to have the same basic dimensions. Has anyone ever tried this? The other choice would be to mill the head and possibly the piston to provide more valve clearance. I figure aroung 1 mm would have to be taken off. Has anyone does these mods? What would a performance shop charge for this kind of work? If you are prepared to run premuim gas all the time this could be the best bang for the buck to get another 6 HP out of her.

[Stu]

--- In DSN_klr650@y..., bkowal@c... wrote: SNIP > The other choice would be to mill the head and possibly the piston to > provide more valve clearance. I figure aroung 1 mm would have to be > taken off. SNIP This seems an easier mod than piston replacement just off the top of my head, but I have a couple of questions; What effect would this have on the cam timing chain? 1mm doesn't sound like much, would the tensioner just take up the slack? As a side note, premium fuel here in CA is now only 91 Octane. Used to be 92 until this June. Cheers CA Stu

[Devon Jarvis]

I have a 10:1 piston in one of my SR500s (stock is 9:1) and it does indeed make a difference. I don't know the differences between the KLR and KLX motors, but the old-fashioned milling the head is a common practice. Remember not only will you have to deepen the valve pockets, but the cam timing will be retarded and you will need modified cam sprockets. There's a guy on the Thumper list who does work like this, Hoyt McKagen. I have never used his services personally, but have heard good things about his work. He has given me lots of good advice about my SR500 in the past. http://batwings.freeyellow.com/best.html An old issue of DSN has an article about hopped-up KLR motors, the guy who built them did compression, bore, stroke, you name it. Don't have the issue handy (or therefore his phone number) but hopefully he's still out there. Anyone else have the back issues handy? Devon bkowal@... wrote:

> The stock KLR has a mild compression ratio of 9.5:1. Most other > large "performance" singles (KTM and KLX) are in the 10.5 to 11.0 > range. Boosting to 11.0:1 would give an easy 16% performance gain. I > figure by running premium gas, the general robustness of the engine, > the water cooling and by adjusting other tuning items (jetting and > plug tempuratures) the reliablilty of the engine would not be > reduced. > > The question is what is the most effective way to boost the > compression. The easiest way would be to replace the stock piston > with an aftermarket performance unit. I have been unable to find a > high compression piston for the KLR. I have noticed that the KLX 650R > has a 10.5:1 ratio. Maybe the piston would fit in the KLR to give it > a boost. It seems to have the same basic dimensions. Has anyone ever > tried this? > > The other choice would be to mill the head and possibly the piston to > provide more valve clearance. I figure aroung 1 mm would have to be > taken off. Has anyone does these mods? What would a performance shop > charge for this kind of work? > > If you are prepared to run premuim gas all the time this could be the > best bang for the buck to get another 6 HP out of her. > > Checkout Dual Sport News at > http://www.dualsportnews.com > Be part of the Adventure! > > 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 > > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/

[twowheelwandering@yahoo.com.au]

> > An old issue of DSN has an article about hopped-up KLR motors, the

guy who

> built them did compression, bore, stroke, you name it. Don't have

the issue

> handy (or therefore his phone number) but hopefully he's still out

there.

> Anyone else have the back issues handy? > > Devon >

That would be Steve Kesselring, very knowledgeable guy. Don't know if he's still into messing with KLR's like he originally was but doesn't hurt to ask. He coated a bunch of components for me and worked out a way to make the lower first gear mod work with a post 96 gearbox. His shop is www.qualityengine-rd.com Rich

> bkowal@c... wrote: > > > The stock KLR has a mild compression ratio of 9.5:1. Most other > > large "performance" singles (KTM and KLX) are in the 10.5 to 11.0 > > range. Boosting to 11.0:1 would give an easy 16% performance

gain. I

> > figure by running premium gas, the general robustness of the

engine,

> > the water cooling and by adjusting other tuning items (jetting and > > plug tempuratures) the reliablilty of the engine would not be > > reduced. > > > > The question is what is the most effective way to boost the > > compression. The easiest way would be to replace the stock piston > > with an aftermarket performance unit. I have been unable to find a > > high compression piston for the KLR. I have noticed that the KLX

650R

> > has a 10.5:1 ratio. Maybe the piston would fit in the KLR to give

it

> > a boost. It seems to have the same basic dimensions. Has anyone

ever

> > tried this? > > > > The other choice would be to mill the head and possibly the

piston to

> > provide more valve clearance. I figure aroung 1 mm would have to

be

> > taken off. Has anyone does these mods? What would a performance

shop

> > charge for this kind of work? > > > > If you are prepared to run premuim gas all the time this could be

the

> > best bang for the buck to get another 6 HP out of her. > > > > Checkout Dual Sport News at > > http://www.dualsportnews.com > > Be part of the Adventure! > > > > Visit the KLR650 archives at > > http://www.listquest.com/lq/search.html?ln=klr650 > > > > Post message: DSN_klr650@y... > > Subscribe: DSN_klr650-subscribe@y... > > Unsubscribe: DSN_klr650-unsubscribe@y... > > List owner: DSN_klr650-owner@y... > > > > Your use of Yahoo! Groups is subject to

http://docs.yahoo.com/info/terms/

[TLrydr@aol.com]

In a message dated 11/7/01 11:50:16 PM EST, jarvisd@... writes: << An old issue of DSN has an article about hopped-up KLR motors, the guy who built them did compression, bore, stroke, you name it >> Where can i get a copy of this mag, I have been signed up for the DSN for the last 2 years, an't seen that issue. Matter fact i have not seen a issue in a long time now. Mike

[Devon Jarvis]

The KLR727 and KLR770 project articles are on the back issues CD, I bought it from DSN and printed it out myself. I forget how much the CD cost but it wasn't much, and I thought it was really worth it. Devon TLrydr@... wrote:

> > In a message dated 11/7/01 11:50:16 PM EST, jarvisd@... writes: > > built them did compression, bore, stroke, you name it >> > > Where can i get a copy of this mag, I have been signed up for the > DSN for the last 2 years, an't seen that issue. Matter fact i have not seen a > issue in a long time now. > > Mike > > Checkout Dual Sport News at > http://www.dualsportnews.com > Be part of the Adventure! > > 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 > > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/

[BCSavWill@cs.com]

Hi, I have been down this road and at some time in the future will get some pistons made, they work out cheaper than stock too and are forged. The quotes I have had are for a batch of 4 with a pattern needed. Any bore oversize and CR in batches of 4. Price complete with rings and pin $155 against Kawa $175 but there is shipping and handling. If the liner will take a 3mm overbore you would get about 690 cc. 2mm is 678cc and 1mm 665. To use a KLX piston you need the R model one at 10.5 cr and this is designed for a nikasil bore (closer fit) by a lot (in piston terms) I have writen about this before, maybe check the archives. Also the included valve angles are different so the valve pockets will be different, don't know about valve diameters but ther KLX KLR par #'s for piston and valves are different for the KLR and KLX and KLX 'R'. Brian KLR A14 KLX C1 TE 410E Honolulu, HI [Non-text portions of this message have been removed]

[Arden Kysely]

I'm hoping to get them off before it rains here in SoCal. I get enough of the near-death stuff from the brain-dead drivers trying to 'borrow' my lane. Arden

--- In DSN_klr650@y..., k650dsn@a... wrote: > --- In DSN_klr650@y..., "Arden Kysely" wrote: > > I've got the Dunlop D606 on the rear and the K139 (now also a D606) > > on the front, and they definitely add to the vibes on the street. I > > did 1000 miles of 50/50 riding on them in Utah, plus maybe another > > 700 assorted miles and the rear is noticeably wearing down. I'd > > estimate it will be toast in another 800 miles. They work great in > > the dirt, but I've had some small slides on the street with the rear > > kicking out under power on corners. Braking suffers some, too. I'd > > say they're best left to those who live close to the dirt and go > > there often. In the city, I'd like more traction. > > > > Arden Kysely > > A11 "Mr. K" > > > > If you really want a near death experience, take them out on wet > pavement. They really get lively then. > > Gino