XR650L: Spud's Oil Cooler

[techforlife]

Originally Posted by Spud Rider

I hope I didn't sound defensive; that was not my intention. I appreciate you feedback, and your concern, Brian. I might do as Red suggested, and pop the caps off the forks as an experiment.

Incidentally, I agree with you regarding the Sutton oil cooler. Mark's oil cooler is not only very functional, it is a work of art. Mark's oil cooler is also, obviously, a labor of love. I doubt Mark makes more than $0.25/hour fabricating all the parts for his excellent oil cooler.

Spud

Nope,,didn`t sound defensive at all Spud,all good here boss....yup..Red has a good suggestion..pull the caps,,it`ll drop like a stone,,then you`ll know for sure..


B

[techforlife]

Originally Posted by Spud Rider

Thanks for the tip, Red. I haven't changed my fork oil yet. How difficult would it be to get the caps back on if I made a quick check in this manner?

A while back someone posted a photograph of his bike with the forks fully compressed after a jump. One can't always tell from photographs, but it sure looked as if the wheel would hit my oil cooler in a similar situation.

Spud

You need to put the bike on a lift of some type....or hang it off a beam in a garage...loosen the caps right off.drop the bike......then all you do is lift the bike back up and screw the caps back on........if you take all weight off the front wheel so it just lifts off the ground there is no spring pressure...

B

[LexLeroy]

Good job Spud. What may be the same cooler, mounted a bit differently and plenty filthy, indicated 240 degree oil in the tank during a 1 1/2 hr. trip home on pavement from the Daniel Boone N.F. Road speed was 65 - 70 mph, ambient air temp was about 75 degrees and the bike is geared 14/45.



Don't sweat a little bit of mud.

[Spud Rider]

Originally Posted by KyoXR

Good job Spud!

we need more fabricators out there doing stuff like this!

don't let the nay-Sayers get you down,(from reading several different forums)

also on a side note,I keep reading about how bad it would be if you got mud on your cooler (from several different forums)...um...the oil will still be cooler then without a oil cooler...to think that somehow getting mud on your oil cooler will make it hotter then running no cooler at all just doesn't make sense.

Thank you, Kyo.

Spud

[Spud Rider]

Originally Posted by techforlife

You need to put the bike on a lift of some type....or hang it off a beam in a garage...loosen the caps right off.drop the bike......then all you do is lift the bike back up and screw the caps back on........if you take all weight off the front wheel so it just lifts off the ground there is no spring pressure...

B

That's what I figured, Brian. I just wanted to make sure. I've been told it's difficult to get the caps back on some forks, and I didn't want to get surprised by my XR650L forks.

Spud

[Spud Rider]

Originally Posted by LexLeroy

Good job Spud. What may be the same cooler, mounted a bit differently and plenty filthy, indicated 240 degree oil in the tank during a 1 1/2 hr. trip home on pavement from the Daniel Boone N.F. Road speed was 65 - 70 mph, ambient air temp was about 75 degrees and the bike is geared 14/45.

Don't sweat a little bit of mud.

Thank you, Leroy. Indeed, I'm not worried about a little mud. I figure the higher I place the oil cooler, the less mud it will accumulate.

My oil cooler is the same as yours, except it's a little smaller. My oil cooler is the 4"X4" version; your oil cooler is the 4"X6" version.

Spud

[ER70S-2]

Originally Posted by KyoXR

Good job Spud!

we need more fabricators out there doing stuff like this!

don't let the nay-Sayers get you down,(from reading several different forums)

also on a side note,I keep reading about how bad it would be if you got mud on your cooler (from several different forums)...um...the oil will still be cooler then without a oil cooler...to think that somehow getting mud on your oil cooler will make it hotter then running no cooler at all just doesn't make sense.

Spud:
I was just stumbling around Thumpers and found your oil cooler project. I agree with Kyo, a good project, and very good pics to show what you're doing. Figure something out, build it, take notes, make improvements if they become necessary, ride. It's projects like this that got man on the moon and robots on Mars.

I had an oil temp gauge in the drain plug (yep, bad location, but a first try) and saw 275* on a slow, hot jeep road. It's also where the oil is hottest; like your choice, before the cooler. But that's why I run full synthetic (Mobil 1 automotive, 15-50). If Suzuki is happy with15-50 dino oil in the DR650, I'm more happy with synthetic. It's my safety factor. And I'm sure that's a whole bucket load cooler than what the NASCAR engines are running. The DR has 2.5 qt capacity, another comfort to me.

Anyway, my suggestion: add another alum strap as high as possible, under the frame tube (red arrow). Even though the cable tie will dampen vibration, it's a weak spot. Keep up the experimenting and I'll tell NASA to look for you here.

Ok, I'm goin' back to the DR650 thread, before I get stoned by Honda riders.

[Spud Rider]

Originally Posted by ThumpnRed

It's easy to see if it will hit. Pull the top caps off the forks and push the wheel up. I am not convinced that it will hit.

Originally Posted by techforlife

You need to put the bike on a lift of some type....or hang it off a beam in a garage...loosen the caps right off.drop the bike......then all you do is lift the bike back up and screw the caps back on........if you take all weight off the front wheel so it just lifts off the ground there is no spring pressure...

B

If the fork caps are removed, the uncompressed springs can extend out the top of the fork tubes, allowing the wheel to rise. However, won't the wheel rise farther than normal without compression of the fork springs?

Spud

[Spud Rider]

Here's a photograph of an XR650L with the suspension bottomed out.



However, the rider, forum member Memnok, has USD forks on his XR650L.

I'm starting to think Red is correct; my oil cooler might not get hit by the tire when the stock forks are fully compressed. I really like the present location of my oil cooler. If necessary, I am willing to limit fork travel.

USD forks bottom out when the outer fork tube contacts the base of the inner fork tube near the front wheel. Do conventional forks bottom out when the outer fork tube contacts the lower triple tree?

Spud

[elsalvadorklr]

spud Im not sure but im pretty sure in the pic of memnok bike, that the outer tube is defintely NOT touching the clamp base of the inner slider where the wheel axle passes

its internally on BOTH styles of forks that you bottom out, spring and cartridge wise

but Im willing to learn more on this scenario, id love to hear some more input from the pro's!

cheers

I was going to post this pic on here saw it posted again on the xrl thread but you got it!

cheers

[elsalvadorklr]

hey spud the reason people have issues with fork caps, is because they dont put their THINKING CAPS on before removing them! wink wink...

you HAVE TO make positively sure that you loosen the top pinch clamp bolts on both sides and sometimes even wedge delicately a flathead screwdriver in the slot to open up the clamp a bit to where you can easily and softly unscrew the caps, same for tightening....

if your forks are stock youlll be amazed when you unscrew those caps off, you actually have negative "preload" on the springs, in other words they are loose in there, if the springs are well used a little shimiing or fork spacer under the cap and between the spring works to eliminate this issue

just thought this might help a bit

[Spud Rider]

Originally Posted by elsalvadorklr

spud Im not sure but im pretty sure in the pic of memnok bike, that the outer tube is defintely NOT touching the clamp base of the inner slider where the wheel axle passes

its internally on BOTH styles of forks that you bottom out, spring and cartridge wise

but Im willing to learn more on this scenario, id love to hear some more input from the pro's!

cheers

I was going to post this pic on here saw it posted again on the xrl thread but you got it!

cheers

Thanks for your input, Christian. I have USD forks on two other motorcycles. On one bike I will bottom out the USD forks occasionally. I think you're correct; the outer fork tube might not hit the lower clamp in that situation, but it comes pretty close.

Originally Posted by elsalvadorklr

hey spud the reason people have issues with fork caps, is because they dont put their THINKING CAPS on before removing them! wink wink...

you HAVE TO make positively sure that you loosen the top pinch clamp bolts on both sides and sometimes even wedge delicately a flathead screwdriver in the slot to open up the clamp a bit to where you can easily and softly unscrew the caps, same for tightening....

if your forks are stock youlll be amazed when you unscrew those caps off, you actually have negative "preload" on the springs, in other words they are loose in there, if the springs are well used a little shimiing or fork spacer under the cap and between the spring works to eliminate this issue

just thought this might help a bit

Thank you, Christian. Indeed, I always loosen all the top pinch bolts in the triple tree, and loosen the fork caps themselves, before I remove the forks for servicing.

I am very willing to remove the fork caps to test if the front wheel contacts my oil cooler. However, it seems if I remove the fork caps, nothing will stop the fork tubes from compressing until the outer tube hits the lower part of the triple tree. Therefore, I'm not sure this test will give me the information I seek. If the fork cap remains screwed to the damping rod (as planned), will the damping rod still limit fork compression with the fork caps removed?

Spud

[elsalvadorklr]

yes!

thats the reason the service manual says to be carefull when unscrewing the lowers from the uppers...

the rod can be damaged...

I think this simple test at least will give you an idea

and in reality its the fork springs and eventual coil binding that will limit your max travel, thats the reason people put stiffer springs, "top out" springs like 88-90xr600 forks have or preload spacers, again preload spacers is more of a cheap fix for initial travel in regards to fork dive when braking hard, not because you dont have enough slider length

look at your bike and measure without the boots and see what you get lengthwise, Ill bet its more than 12 inches

actual fork travel on our bikes is 11.8 inches...less when taking into account sag and all

[Spud Rider]

Yesterday I decided to figure out how much the forks could compress before the front wheel impacted my oil cooler. I removed the front fender, placed my XR650L on a stand, and measured the free sag at 1-1/8 inches. Taking the bike off the stand, I measured the travel from the wheel to the bottom of the oil cooler at 9-1/2 inches.



Adding the free sag to the last measurement, I got a total wheel travel of 10-5/8 inches. Therefore, the wheel will impact my oil cooler in the last inch of travel. I'm convinced 10-5/8 inches of fork travel is sufficient for the way I ride my XR650L, so I have decided my oil cooler is positioned high enough. Incidentally, I raised my forks one inch when I installed my lowering link. Therefore, a stock bike would be able to accommodate maximum fork compression without striking my oil cooler.

Since the weather was nice, I rode my XR650L for 56 miles on the freeway, without the fender, to discover the highest level of cooling I could expect.



I maintained 75-80 mph the entire time, and passed a lot of automobiles along the way. My oil temperatures did not exceed 255 degrees; I am pleased with this result. Of course, once I exited the freeway, my oil temperatures quickly dropped to much lower levels.



I am going to trim my front fender a bit more, to ensure the wheel will not impact the fender before it would impact the oil cooler. I will also drill a few more holes in the fender, and test to discover if the drilled fender allows cooling similar to a fenderless setup. If the cooling is significantly less with my drilled fender, I will cut a large hole in the fender and install some aluminum hardware cloth.

Spud

[Cumbacheech]

Originally Posted by Spud Rider

Since the weather was nice, I rode my XR650L for 56 miles on the freeway, without the fender, to discover the highest level of cooling I could expect.



I maintained 75-80 mph the entire time, and passed a lot of automobiles along the way. My oil temperatures did not exceed 255 degrees; I am pleased with this result. Of course, once I exited the freeway, my oil temperatures quickly dropped to much lower levels.



I am going to trim my front fender a bit more, to ensure the wheel will not impact the fender before it would impact the oil cooler. I will also drill a few more holes in the fender, and test to discover if the drilled fender allows cooling similar to a fenderless setup. If the cooling is significantly less with my drilled fender, I will cut a large hole in the fender and install some aluminum hardware cloth.

Spud

Spud,

Bike looks bad ass with no front fender... maybe a low front fender is in order...