Wheel Alignment on my 961.

lcrken

VIP MEMBER
Joined
Mar 15, 2009
Messages
4,430
Country flag
Got the forks back together and the bike is ready for a trial run.

Bike with Straightened Forks 1200.jpg


Can't tell from looking that the forks were ever bent. I did raise the forks in the yokes a very slight amount, just enough to hide the bend line.

Straigntened Forks 1200.jpg


For anyone interested in disassembling the conventional Ohlins forks, there are some special tools required. Instead of trying to find the Ohlins tools, I made my own, shown below. Top to bottom, they are the seal and bushing installer, a socket to remove and install the cartridge assembly, and a tube with a nut on the end to pull the damper rod up during assembly. The last two are pretty cobby, but they work.

Ohlins Tools 1200.jpg




I checked the front to rear wheel alignment, and was able to adjust the rear wheel to get them in line, but there is still a difference in distance between axle slider and end of swinging arm of 0.10". Way better than the 0.325" difference I started with, but still more than it should be. I wouldn't be surprised if there is still something else that got a little bent, like the steering head area of the frame. I'll do some test riding, and if I don't find any handling problems, it will stay as is for a while so I can keep riding it. Somewhere down the road I'll probably have the engine out for a tear down, and I can get the frame checked then.

I did find out something kind of interesting in the process. The front axle appears to be hollow, but it isn't. It's only drilled part way from the ends, apparently just for appearance. I drilled it all the way through, and saved 10 oz. of unsprung weight, not much in terms of overall weight reduction, but a significant amount in terms of front wheel control. Turns out they did the rear axle the same way, so I can look forward to drilling it through the next time I change the tire. Of course a real fanatic would have just made a titanium replacement. I did consider that, but making Ti axles with my equipment is pretty slow, and I really wanted to get the bike back on the road. A future project, maybe.

Ken
 
Joined
Jan 16, 2015
Messages
4,018
Country flag
Got the forks back together and the bike is ready for a trial run.

View attachment 81631

Can't tell from looking that the forks were ever bent. I did raise the forks in the yokes a very slight amount, just enough to hide the bend line.

View attachment 81632

For anyone interested in disassembling the conventional Ohlins forks, there are some special tools required. Instead of trying to find the Ohlins tools, I made my own, shown below. Top to bottom, they are the seal and bushing installer, a socket to remove and install the cartridge assembly, and a tube with a nut on the end to pull the damper rod up during assembly. The last two are pretty cobby, but they work.

View attachment 81633



I checked the front to rear wheel alignment, and was able to adjust the rear wheel to get them in line, but there is still a difference in distance between axle slider and end of swinging arm of 0.10". Way better than the 0.325" difference I started with, but still more than it should be. I wouldn't be surprised if there is still something else that got a little bent, like the steering head area of the frame. I'll do some test riding, and if I don't find any handling problems, it will stay as is for a while so I can keep riding it. Somewhere down the road I'll probably have the engine out for a tear down, and I can get the frame checked then.

I did find out something kind of interesting in the process. The front axle appears to be hollow, but it isn't. It's only drilled part way from the ends, apparently just for appearance. I drilled it all the way through, and saved 10 oz. of unsprung weight, not much in terms of overall weight reduction, but a significant amount in terms of front wheel control. Turns out they did the rear axle the same way, so I can look forward to drilling it through the next time I change the tire. Of course a real fanatic would have just made a titanium replacement. I did consider that, but making Ti axles with my equipment is pretty slow, and I really wanted to get the bike back on the road. A future project, maybe.

Ken
Awesome work Ken , You make it seem easy !
 
Top