Took a plunge... trying a PP LXR250 EFI

[ChondaChondaChonda]

Originally Posted by OUTERLIMITS

Anything new on this? I'm guessing you are continuing on with your fix from the day before. Hoping this works out for you and can carry you the rest of the way.

I have a theory... it only happens when we do an extremely long climb and then hit a steeper climb; I think the clutch Springs are getting weak when the oil is too hot, combined with the clutch rod growing the pressure plate starts slipping, which makes more heat...
It did well today. No issues since we put the thrust washer back and ground a mm off the push rod.
I

[OUTERLIMITS]

Originally Posted by ChondaChondaChonda

I have a theory... it only happens when we do an extremely long climb and then hit a steeper climb; I think the clutch Springs are getting weak when the oil is too hot, combined with the clutch rod growing the pressure plate starts slipping, which makes more heat...
It did well today. No issues since we put the thrust washer back and ground a mm off the push rod.
I

I wonder what engine is the closest cousin that you may be able to find some heavier clutch springs for.

[ChondaChondaChonda]

I like the way you think.
Will be looking after we either finish this ride, or it finishes us.

[Ariel Red Hunter]

Originally Posted by OUTERLIMITS

I wonder what engine is the closest cousin that you may be able to find some heavier clutch springs for.

I don't know the construction of your clutch, but, so far, there are really only two ways to dis-engage a multi-plate motor cycle clutch. A push rod, operated by a lever, from the opposite side, or a screw operated ramp, often from the same side as the clutch. Almost all interpose a ball between the ramp or lever and the actual release mechanism. If the adjuster on the crankcase does not have enough clearance (1/8th of an inch), the ball locks, while hot, to the release mechanism. This allows the internal mechanism to get extremely hot, which makes the metal grow, and semi release the clutch, causing slippage. Of course, as the clutch slips it gets hotter and hotter. This could be aggravated by a machining burr in the lever housing, or inadequete spring tension on the outside lever on top of the crankcase...ARH

[OUTERLIMITS]

Originally Posted by Ariel Red Hunter

I don't know the construction of your clutch, but, so far, there are really only two ways to dis-engage a multi-plate motor cycle clutch. A push rod, operated by a lever, from the opposite side, or a screw operated ramp, often from the same side as the clutch. Almost all interpose a ball between the ramp or lever and the actual release mechanism. If the adjuster on the crankcase does not have enough clearance (1/8th of an inch), the ball locks, while hot, to the release mechanism. This allows the internal mechanism to get extremely hot, which makes the metal grow, and semi release the clutch, causing slippage. Of course, as the clutch slips it gets hotter and hotter. This could be aggravated by a machining burr in the lever housing, or inadequete spring tension on the outside lever on top of the crankcase...ARH

That's a great explanation! I had a friend with an XR400 do an overnight ride with me and some others into baja. Somewhere before the end of the first day his clutch became so stiff that you couldn't pull it in for fear of breaking the cable and it made a horrible groaning sound if you did manage to pull it in. We had a number of other dirt bike riders look at it at the hotel and they all just kind of scratched their heads. He rode home the next day not using the clutch except from a stop. He replaced the clutch with new plates and such and all was well, but we never understood why it took such extreme pressure at the lever. I'm not a clutch guy at all, but it felt like the springs had turned to stone. He only replaced the drive and friction plates I believe and then all was well.

[ChondaChondaChonda]

I just went over 10,420ft pass called Railroad Ridge which has a mountain range behind it called China Wall. Clutch is doing fine now. Zero issues after trimming the push rod.

[ChondaChondaChonda]

[ChondaChondaChonda]

I just posted a picture of my China bike at China Wall on Chinariders... say THAT 5 times fast!

[pete]

Originally Posted by Ariel Red Hunter

I don't know the construction of your clutch, but, so far, there are really only two ways to dis-engage a multi-plate motor cycle clutch. A push rod, operated by a lever, from the opposite side, or a screw operated ramp, often from the same side as the clutch. Almost all interpose a ball between the ramp or lever and the actual release mechanism. If the adjuster on the crankcase does not have enough clearance (1/8th of an inch), the ball locks, while hot, to the release mechanism. This allows the internal mechanism to get extremely hot, which makes the metal grow, and semi release the clutch, causing slippage. Of course, as the clutch slips it gets hotter and hotter. This could be aggravated by a machining burr in the lever housing, or inadequete spring tension on the outside lever on top of the crankcase...ARH

or a rack & pinion .. that pulls the pressure plate...
ie.... XT660R / TTR250 & most Yamaha dirt bikes to name a very few..




.

[OUTERLIMITS]

Chonda, any more updates?

[ChondaChondaChonda]

We made it to the Sundance Outlook this afternoon. The bike has been flawless since the little clutch issue. Nearly 1800 miles of abuse and it runs better now than when we left 10 days ago.

It has been an amazing trip. A few minor crashes, some close calls. Saw a grizzly cub in the wild. Saw bighorn sheep herd from about 30 yards away. Lots of elk and deer. 2 foxes. Rode some gnarly singletrack that was way above my skill level. Nearly broke my arm. Lots more than I can fit in a post.

If you look at my map link above you can zoom in and see all the trails we rode in 9 days of the challenge. The Pitster Pro not only did well, it rocked! As we progressed the bike seemed to finally break in and runs far better than the day we left. Many of the trails we did were first gear, death grip, don't fall off a cliff kind of trails-we averaged about 10 hours of riding per day. Day7 took us 16 hours to complete...

The bikes worst mileage was Day1 at 48mpg. Most days it did 55-59mpg. On a long transfer day crossing the Magruder Corridor it managed 61mpg.

The other thing I love about this bike is how well it chugs through at low rpm. Many climbs the bike lugged down and pulled me up some incredibly technical sections. This made me look aND feel like a better rider than I am. The bike inspired confidence, which is what I needed to complete this challenge.

[goat67]

Way to go! Post some more about it. Again great job. You accomplished something to be proud of.

[ChondaChondaChonda]

[ChondaChondaChonda]

[ChondaChondaChonda]

This what 505 tires look like at 1800 miles. Mine is a 120, my buddies a 110.