70+ Hp Xr650l

I didn't want to hound you about it and besides, I only just remembered myself. I asked about the steel ring mentioned here:

we did see issues with horizontal cracks in our cases running from the crank bearing to the countershaft bearing but we seemed to have cured that by installing a steel ring behind the crank bearing. now it can take a pretty heavy pounding:bonk:

Since you are so good at finding incriminating info. Can you find me a link for using photobucket.

Well, you can send it to me via email and I will host it and post here(via my phobucket) or you can go to photobucket.com and create your own picture hosting account.

That's the only way to do it. You need an account in order to use it.

I will get an account on monday when I get back with some lobster.

here is the picture of the steel ring that we installed to prevent the horisontal cracking. We have since started using a aluminium ring made of 7075 with less holes and have not had a problem either.garage.php?do=viewattachment&attachmentid=53404

I can't thank you enough for sharing that! :cool:

here is the picture of the steel ring that we installed to prevent the horisontal cracking. We have since started using a aluminium ring made of 7075 with less holes and have not had a problem either.garage.php?do=viewattachment&attachmentid=53404

Is the spacer in the picture for a longer rod, or longer stroke?

Id guess its to get the deck height right for that big mutha of a piston on their bikes!

Thats some very impressive stuff there Stepho. I would drop everything and move there if you would ever need another Tech!!!

brtp4,

I have a prgrammabvle CDI that Im fitting to the XRL at the moment. I expect itll give me more midrange and top end drive with the higher RON fuel we can get here at UK pumps.

Ive also removed the starter gear and clutch on my bike - this makes a massive difference to bttom end response and I personally think a lot of the bottom end pickup differences btwn XRL's and XR's is cos of this. Im now running as total loss system (no Gen rotor) and the acceleration is very good.....it needed stiffer clutch springs to cope :thumbsup:

How about some info. on your programmable cdi, how did that come out, what components is it made up of?

For those of you getting excited about HP and torque #'s,remember you can only go so far.

IMO, you should be looking at weight to power ratios and HP#'s to $$$ ratio.

Just y .02

Fab Shack Racing (board name) does sum crazy chit w/ XR650L motors...i traded a few PM's with him last week...i hope he doesn't mind but i'll share sum of his stuff...

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"...people don't seem to believe I can build 80 h/p N/A xrl motors, LOL...The motor I just built last month for the orange bike is stroked 5mm and 105.5 mm bore (761cc's), it hauls the mail pretty good..."

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"The dune Warrior (above) is a mild build, ride all day and reliable, stock stroke, 102mm bore, 670cc's, web cam, ported head,41mm carb, have not dyno'ed this build because its not one of my race motors, but it probably has around 55 h/p I would guess."

:thumbsup:

Once you start stroking the engine along with the over bore you enter a whole different demention:crazy: Not for the faint at heart engine biulder or those low on cash. These are not daily mail carriers......they may carry the mail at warp speed but, not out to the mine shafts of yester year in the middle of the Mojavi desert 60 miles further then nowhere. I have delt with the rod and crank of the XR600R for way to long and have seen the end result of the stroked motor many times. It works and it is a race engine, with it's biult in risks. I think it comes down to 50~52 rwhp (about 64bhp) for a XR650L engine to carry the mail every day and be bullet proof. If it is for race with the $$$ to support it then as you have shown 62+rwhp, (80bhp) not force feed can be done, I am sure even more. One thing we have found is that Dyno number with the same engine are much high if the engine is in a quad in fourth then in a bike in fourth.

no doubt...

i wus asking him about the "milder" build...none the less his NA race motor is pretty impressive, at least in my book.

:thumbsup:

P.S. ...and i wud not looking for peak HP...i wud prefer "fattening" up the curve across the board.

That 761 is bad ass.

I think all you need is a cam, hi comp overbore piston, slide pumper, good exhaust and some mild porting to have a reliable, haul the mail L motor.

For those of you getting excited about HP and torque #'s,remember you can only go so far.

IMO, you should be looking at weight to power ratios and HP#'s to $$$ ratio.

Just y .02

The unfortunate case for big XRs is that reducing a worthwhile amount of weight is going to cost more than buying enough power to make up for carrying that weight.

Assuming a bike alone weighs 320lbs, it is hauling 7.6lbs/hp at 42bhp, but only 5.8lbs/hp at 55bhp. If the power was left at 42, the bike would have to lose 75.6lbs to match the 320lb, 55hp bike. That's BBR aluminum frame territory.

That 761 is bad ass.

I think all you need is a cam, hi comp overbore piston, slide pumper, good exhaust and some mild porting to have a reliable, haul the mail L motor.

I would agree with that and maybe add oil cooler, bigger fins, clutch springs. Once you stroke the XR engine the rod is stressed to much for a bike you would beat to death out in the boonies. I left the "r" out of "stroking" and it read wrong. I love fast "squeeze every last bit of power" engines but, not really what the XR650L was made for. The stock "L" suck for what it could be that is for sure but, like Martinfan said, over bore, 10.25:1 piston, cam and a pumper carb. and the bike will take you around the world......twice!

I assume thats a turbo off of a Seca 650 turbo?

I've never seen the specs on them, but just looking at the compressor diameter, thats a pretty big compressor (which surprises me)

Just a rough guess, but that turbo is probably good to 150 hp or so. A little bigger than I'd want to go unless its an all out race bike

where in WA are you anyway?

I assume thats a turbo off of a Seca 650 turbo?

I've never seen the specs on them, but just looking at the compressor diameter, thats a pretty big compressor (which surprises me)

Just a rough guess, but that turbo is probably good to 150 hp or so. A little bigger than I'd want to go unless its an all out race bike

where in WA are you anyway?

You´re Uncle Bob on SMJ, right?you had a really good thread on SMJ about your turbo´DRZ400...How are you?I mean... your bike? :thumbsup:

You´re Uncle Bob on SMJ, right?you had a really good thread on SMJ about your turbo´DRZ400...How are you?I mean... your bike? :thumbsup:

the same

the bike has been doing really good until a recent episode

Turned out to be nothing major thankfully

http://www.thumpertalk.com/forum/showthread.php?t=662832

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