KLX 650C PISTON - 685 KIT

[klx650realdeal]

I've been looking for an oversize piston for my KLX650C model with no luck in the States - 2 in Europe for a very large price.  So.... I sent my old piston to Cary at Schnitz Racing and he called me within a day of receiving it and gave me the bad news; their 685 piston for the KLR was similar but would give me a compression ratio of about 16:1!  Not good. 

Kudos to Cary for the quick response, couldn't have asked for better service.  His suggestion is I find 5 other lucky feller's with the same model and have JE make up 6 of these in an oversize so that they are available here in the States.

I hear that the Vulcan 1500/1600 piston may work; is anybody 100% sure of this?  Many people get the KLR and the KLX mixed up; they are significantly different engines.

Thanks,

Todd
 

[Hondo]

Hey Todd- I'd post up at ADV Forums/Thumpers to see if anyone else there might be interested in getting the new O/S pistons made.

[Rico]

16:1 huh? You could always make a diesel. 

[itsatdm]

  I just installed a Wossner 102mm piston in my 1995 KLX650c for 680cc (ok 678.4cc) similiar to the 685, in that it is short skirted, forged  aluminum.  From the measurements I took it will have about the same compression as the stocker and it weighs about 73 grms less than stock.  Purchased from LA Sleeve for $185  which includes rings and piston pin.  A local did the rebore and hone for $80.  Total price ended up about the same as the KLR685 kit. 
  Have about 500 miles on it.  The bike has improved torque and runs smoother.  Used no oil so far.

[Hondo]

Thanks for posting up that info.

Looks like you've solved the issue! 

Which kit did you get?

Here's a link to LA Sleeve-

http://www.lasleeve.cc/index.cfm?manufacturer=Wossner&manufacturer_ID=15

[gunny]

excellent tip itsatdm 

[klx650realdeal]

Nice - guess I should have posted my woes a while ago!

T

[itsatdm]

 It may not be on the LA sleeve website yet as they just took over the Wossner line of pistons.  I found it on the Wossner germany site.  Made specifically for the KLX 650.  Comes in standard, 101 and 102 overbores.  But LA Sleeve is aware of it and can order it for you, just be sure you tell them you want a Wossner piston.  Took about 2 weeks to deliver. 

[itsatdm]

  Thought  I would update this thread as I have just added a few miles to the bike on the dirt roads of Death Valley.  Due to a mishap, I also got to ride a KLR in the dirt for about 50 miles, so I thought a comparison was in order.  First of all my mishap was a crash that took out my electricals and not motor related. 
  Re: the KLR, I now know why some describe the KLR motor as a tractor.  It is very torquey at low to medium rpm.   Upto legal highway speed it had little trouble staying with the KLX680.  They were evenly matched.  On long steep straightaways the KLX would pull away and had much better passing power at higher rpm.  I have never checked the cam profiles, but the KLX obviously breathes better at higher rpm.  I never considered the KLX a shaker, but the lighter piston still managed a smoother motor upto about 75mph and even then I only felt some vibes through the footpegs.  Over 7000 rpm the motor felt harsher than before, I supposed it is a trade off for the less vibration below that.  The KLR began to vibrate at about 65mph and i could feel in the pegs, handlebars and seat. The faster you went the more noticeable it was.
  I have an after market windscreen and front fender on the KLX and it handled wind better than the KLR with a taller windscreen on a windy day.    It tracked very straight and deflected wind well.  The KLR dumped right at shoulder level.
  Off road, The KLX felt much lighter than the 30# difference would lead you to expect.  It just felt nimble, just like a dirtbike.  Loose sand and rock made the KLR scary on some of the same terrain. I am sure a rider could get used to it, but the fixed cowl, large tank and inability to see what the front end was doing was disconcerning.  The KLR had stock suspension and it did seem to handle the uphill washboards better than my KLX.
  I like the KLR and with the right mods, think it would be a good all around bike.  But I still prefer my KLX the way I have modded it.  Some wind protection, wider seat and a 5 gal tank, it will cruise at least as good and probably better the the stock KLR.  At normal highway speeds it still returned 51 mpg.  Neither are the bike of choice for hardcore off road, but the KLX will go through the medium level stuff at a higher rate of speed and still feel like you are in control.   That said, I still crashed it.  Rider error resulted in a laydown next to a large boulder that hit the cowl pushing my tach into the steering stem and shorting out my CDI.  If anyone knows of a used one available, I would appreciate the info.

[klx650realdeal]

Just received an email the other day from LA Sleeve with the part numbers for the KLX650C pistons:

8512DA    STD    99.94mm
8512DB    +0.01    99.95mm
8512DC    +0.02    99.96mm
8512D100    +1.0    100.94mm
8512D200    +2.0    101.94mm
 
Hope this helps others!

Price is $184.90

Todd

[Hondo]

Going to sticky this-

[Maverick]

LA Sleeve is where Bill Blue gets his pistons from for the 331 kit AFAIK

[KLRCARY]

 We are offering the Wossner pistons now too, on a special order basis. They have a 1.00mm over to fit the earlier (87-95) klr's, and for the 600 also. It's a nice piston.

[icehose]

itsatdm: where did you get the 5 gal tank for your KLX650?  I'm negotiating to buy a '95 down in Costa Rica and sure would like to upgrade to a larger capacity tank (lot's of back roads in CR with gas pumps few and far between).  Also, the wind screen?  I already have an '03 KLR650 down there but expect the KLX to perform better in the back country (which is pretty much where I prefer to ride).

[SLO-KLR]

  icehose!

[itsatdm]

I suspect the tanks are unobtainable again.  I got one of a special run of 15 made by Aceribis by some one who who someone.  They are pretty rare on the used market.  Before that I used a baja design side mount tank meant for a Yamaha.  http://itsatdm.smugmug.com/photos/77759514_SM65a-M.

[itsatdm]

I got lucky with the tank.  Somebody who knew somebody at Aceribis got a special run of 15 made and I got one.  Only hope now is the used market.
Before that I used a side mounted Baja Design tank meant for a Yamaha.  Gave 4.5 gals total but required a fuel pump.  jpg

[cbleicester]

I got lucky with the tank.  Somebody who knew somebody at Aceribis got a special run of 15 made and I got one.  Only hope now is the used market.
Before that I used a side mounted Baja Design tank meant for a Yamaha.  Gave 4.5 gals total but required a fuel pump.  jpg

I'm now on a quest to find an Acerbis tank for my KLX650C ... could be a long one! I've been looking a RotoPak flat gas tanks, but the Baja Designs item you fitted looks neat. Dis you have to modify much to fit it? And what did you do with the coolant header tank that's behind the stock nearside side panel?
And if you don't mind another question - what is the make/model of the screen on your bike?
Thanks in advance!
Chris

[klx650realdeal]

Check out these windshields:  http://www.ceebaileys.com/acerbis/index.html

KLX650REALDEAL

I have an Acerbis tank.  Be careful as there is a tank for the R as well as the C.  You can put an R tank on but need the seat as well.

[itsatdm]

The side tank fit with two small brackets, one on the passenger peg mount, the other attached to the seat/fender mount.  You can see the "new" coolent tank.  A 1 pint water bottle, stuck in the skid plate near the tool holder.  The windshield is a Maier universal sport.

[Bathy]

I've been looking for an oversize piston for my KLX650C model with no luck in the States - 2 in Europe for a very large price.  So.... I sent my old piston to Cary at Schnitz Racing and he called me within a day of receiving it and gave me the bad news; their 685 piston for the KLR was similar but would give me a compression ratio of about 16:1!  Not good.  

Kudos to Cary for the quick response, couldn't have asked for better service.  His suggestion is I find 5 other lucky feller's with the same model and have JE make up 6 of these in an oversize so that they are available here in the States.

I hear that the Vulcan 1500/1600 piston may work; is anybody 100% sure of this?  Many people get the KLR and the KLX mixed up; they are significantly different engines.

Thanks,

Todd
 

I know this is old thread, but........

I have the vulcan 1500 piston in my KLX650R.
slightly different dish shape, but it works fine.
I got 2 pistons for a carton of beer from the local dealer,
from a warranty job they were doing on a near new Vulcan.
took it out to 678cc

However in the never ending search for more power i'm interested in the 705 kit for the KLR.

I see the KLR piston is a flat-top design were as the KLX is dished.
so................ is that the source of the bump in compression up to 16:1

or is the piston crown height from the gudgeon significantly higher than the KLX piston?

I am also curious to know if they KLR and KLX run the same diameter gudgeon pin.

If somebody could post some specs on a KLR piston i'd really appreciate it, namely the gudgeon diameter and gudgeon to crown distance.

I wonder if the 705 piston has enough material left in the crown to have a dish machined?

or perhaps a barrel spacer of say 3mm could be used to increase the compression chamber and lower the comp. ratio?

Here's pics of a KLX piston with a vulcan piston.

[cozymoto]

Dear everyone.

i use KLX 650 c 95'
I have problem of my piston break down due to water drop got inside piston
i wonder where can i find VN1500 piston or anyone has another piston? i am in Thailand so it's real hard to find both stock and VN 1500

will go up to 102 mm this time

one more things my cam cover is running slightly worn, how to do then? (removed decompressed already)

Thanks everyone
Email: cozystore@hotmail.com