radman
R.I.P. Our Motorcycling Friend
Some here may know of Franks final drive leak I commented on in another thread here. Well, pulled him apart and repaired today. Wish all fixes were this easy.
The final ready for disassembly. Leak was thought to be at the seal around the ring gear, which is what the wheel hooks to via a splined connection anyone who's changed their own tires is familiar with. When I removed the wheel, the seal was dry and clean. What was leaking was the large o-ring that seals the ring housing to the final drive unit. Once all the nuts and the two bolts (frontal area) are removed, gently, evenly pry the assembly free. DON'T LET IT POP OUT AND FALL!!! Easy does it there Hercules. The lower of the two bolts came out very hard-I feared WC's Sumo guy had moved down the assembly line to final drive area, and fully expected to find the bolt threads liberally coated with aluminum. Thankfully, wasn't the case. Went back in just as hard, but accepted correct torque without complaint.
The ring gear assembly. The offending o-ring fits around the outside edge in a machined groove. Note the nice wear pattern on the ring gear teeth.
The final housing exposed. Note the washer sitting near center-this is a thrust washer that fits over the ring gear snout. Forget to re-install it and in it's original orientation, and you will become familiar with University Motors low low pricing and friendly customer service. Rather than cleaning out the quite spotless housing, I left it as is, everything was nice and clean already, and well lubed-better to leave it this way. Already removed was the gray plastic dust shield, be sure to re-install if you've taken it out-it just pops in and out, though only one way-be sure to orient it correctly. Just for giggles, I located and back-flushed with 3M 08880 brake clean, the only Rad-Approved® brake cleaner, the vent hole, which vents into the smaller area just above the small bearing housing (you can see the casting bulge leading up to it) All nice and clear.
The new o-ring and our friend Mr Mobil 1.
Coat the o-ring and the housing with a liberal dose of M1 grease for ease of assembly as well as o-ring protection upon installation. Don't forget to grease up the small seal on the other side of the drive, which is next to the roller bearing still in the housing.
When inserting the ring gear assembly back in, apply pressure evenly and gently until the housing settles in-you may likely need to turn the ring gear via the splines to allow mating with the pinion, necessary due to the helical design. No need to mark positions or anything-all the teeth are pals. Don't forget the thrust washer! Cross torque the nuts and the two bolts, nuts at 14 lbs, bolts to 29 lbs.
All back together. Note the job was done with the final drive in the bike-a real plus as the bike made for a nice steady platform, no need to remove unless pinion seal service is also required. The wheel is actually doing 35 mph in this pic, gotta love fast cameras. Since the ring gear is pressed into the bearing in the housing, and the shim pack is part of this, there is nothing to fear concerning re-setting the gear lash, so it's pretty easy to do. If the seal I originally suspected of leaking does indeed weep come hot weather and fast riding, I wouldn't hesitate to pull it all apart again and pop it out and replace. The o-ring and seal are about $12 outta U motors, hardly worth having a dealer do it, with all the crap and downtime associated with that tactic, warranty or no. I do have the YES, but it's for major crap only, tic-toc, should I ever need it. At 28 thou, Frank has been reliable as a stone, and but for the recall TPS, has yet to have some furriners fingers massaging his innards. He likes this, and has communicated to me my methods are fine by him......
The final ready for disassembly. Leak was thought to be at the seal around the ring gear, which is what the wheel hooks to via a splined connection anyone who's changed their own tires is familiar with. When I removed the wheel, the seal was dry and clean. What was leaking was the large o-ring that seals the ring housing to the final drive unit. Once all the nuts and the two bolts (frontal area) are removed, gently, evenly pry the assembly free. DON'T LET IT POP OUT AND FALL!!! Easy does it there Hercules. The lower of the two bolts came out very hard-I feared WC's Sumo guy had moved down the assembly line to final drive area, and fully expected to find the bolt threads liberally coated with aluminum. Thankfully, wasn't the case. Went back in just as hard, but accepted correct torque without complaint.
The ring gear assembly. The offending o-ring fits around the outside edge in a machined groove. Note the nice wear pattern on the ring gear teeth.
The final housing exposed. Note the washer sitting near center-this is a thrust washer that fits over the ring gear snout. Forget to re-install it and in it's original orientation, and you will become familiar with University Motors low low pricing and friendly customer service. Rather than cleaning out the quite spotless housing, I left it as is, everything was nice and clean already, and well lubed-better to leave it this way. Already removed was the gray plastic dust shield, be sure to re-install if you've taken it out-it just pops in and out, though only one way-be sure to orient it correctly. Just for giggles, I located and back-flushed with 3M 08880 brake clean, the only Rad-Approved® brake cleaner, the vent hole, which vents into the smaller area just above the small bearing housing (you can see the casting bulge leading up to it) All nice and clear.
The new o-ring and our friend Mr Mobil 1.
Coat the o-ring and the housing with a liberal dose of M1 grease for ease of assembly as well as o-ring protection upon installation. Don't forget to grease up the small seal on the other side of the drive, which is next to the roller bearing still in the housing.
When inserting the ring gear assembly back in, apply pressure evenly and gently until the housing settles in-you may likely need to turn the ring gear via the splines to allow mating with the pinion, necessary due to the helical design. No need to mark positions or anything-all the teeth are pals. Don't forget the thrust washer! Cross torque the nuts and the two bolts, nuts at 14 lbs, bolts to 29 lbs.
All back together. Note the job was done with the final drive in the bike-a real plus as the bike made for a nice steady platform, no need to remove unless pinion seal service is also required. The wheel is actually doing 35 mph in this pic, gotta love fast cameras. Since the ring gear is pressed into the bearing in the housing, and the shim pack is part of this, there is nothing to fear concerning re-setting the gear lash, so it's pretty easy to do. If the seal I originally suspected of leaking does indeed weep come hot weather and fast riding, I wouldn't hesitate to pull it all apart again and pop it out and replace. The o-ring and seal are about $12 outta U motors, hardly worth having a dealer do it, with all the crap and downtime associated with that tactic, warranty or no. I do have the YES, but it's for major crap only, tic-toc, should I ever need it. At 28 thou, Frank has been reliable as a stone, and but for the recall TPS, has yet to have some furriners fingers massaging his innards. He likes this, and has communicated to me my methods are fine by him......
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