Front fork removal oil seepage

[asmith411]

My son and I removed the front fork from our 1967/68 250 Scrambler. Unfortunately, I rested the fork down horizontally and noticed oil/fluid seeping from the top tubes. I immediately positioned the fork vertically, but lost about 2 ounces of fluid from each tube. The fluid looks and smells like motor oil. Should I pour some fluid into the tubes? Looking for some help with this situation.

Thanks,
Art

[tobydmv]

I would take the opportunity to change the fork oil and maybe see why the oil leaked out. The manual has the specs. Tons of options at your local cycle shop or just use ATF or any 10-20wt oil.

[asmith411]

Is there a manual available on line for a 250 wide case single?
Thanks for your comment.

Art

[asmith411]

I would take the opportunity to change the fork oil and maybe see why the oil leaked out. The manual has the specs. Tons of options at your local cycle shop or just use ATF or any 10-20wt oil.

.......Can you be more specific with the changing of the front shock oil. The manual says to pour the shock oil down the tube, so that would lead me to believe that the oil could leak out if laid out horizontally. Could I just drain the remaining oil from each shock and place 3 1/2 ounces of new hydraulic brake fluid down each tube. The dismantling and reassembly seems rather detailed and time consuming, as well as confusing. I'm hoping I can do this without dismantling the forks.

Thanks,
Art

[JimF]

I do believe that you are correct, the fork oil can and will just run out if the tubes are laid down or tipped.

If you want to just drain them and add more oil/ATF you can do that.

You can fabricate a tool to hold a pin in the bottom of the forks from turning if you ever want to take them apart. I made mine out of a piece of threaded rod using a hacksaw to make the notch. The bend at the other end is simply so you can hold the rod and keep it from turning as you take the cap screw of the bottom of the fork leg

Fork_tool.JPG

Fork_tool_tip.JPG

[asmith411]

Thanks for your help. I feel much better not having to disassemble the forks.

Art

[tobydmv]

.......Can you be more specific with the changing of the front shock oil. The manual says to pour the shock oil down the tube, so that would lead me to believe that the oil could leak out if laid out horizontally. Could I just drain the remaining oil from each shock and place 3 1/2 ounces of new hydraulic brake fluid down each tube. The dismantling and reassembly seems rather detailed and time consuming, as well as confusing. I'm hoping I can do this without dismantling the forks.

Thanks,
Art

Art, its extremely easy and simple to dissasemble. My bicycle forks are 5x more complicated, ok maybe 10x more complicated. Ever seen the insides of a fox float rlc?

To drain, remove the screw on the side of each leg. To fill, remove the fork plug from the top of each leg and pour in. Manual has the specs to keep it clean. To disasemble there is one hex screw holding the pumping rod to the stanchions/sliders. Use a cordless drill with a hex bit and the pumping rod should not rotate. If it does remove the oil drain screw and rotate the pumping rod. I believe there is a hole in the pumping rod that will align with the drain hole with some effort. You can then insert a very small hex wrench to keep the rod from spinning or hold it from above like Jim mentioned.

[JimF]

+1 on the simplicity factor of these forks.

You cringe as you think you are going to open some complex hydraulic mechanism that you will neither understand or be able to put back together and when you pull out the fork innards you almost laugh. Pulling the forks apart gives you a chance to clean them up but to be honest I think so long as some hydraulic fluid was always present the fork internals will be clean and shiny.

I think the better reason to pull the forks apart is to check the straightness of the fork tubes. I have pulled two or three sets apart and as I recall out of the four or six tubes only one was straight when checked on a granite slab. I gather that a 31.5mm fork tube is widely considered 'spindly.' I believe Ducati went to 32mm (or was it larger) on the last series of the wide case singles. Suffice it to say they used a fork tube that was bigger than 31.5mm.

I can get the name of where I sent mine to be straightened if you want it. I believe they use a several ton hydraulic press and V-blocks along with some skill. I checked my tubes when I got them back on the granite table and they were straight as an arrow.

It cost more to ship them (weight and girth, round trip) than to have them straightened.

Does it make a difference if they are straight versus a little bent? I can't say. I may have ridden a bike with bent fork tubes and never known it. It's just a piece of mind thing that you can do while you "are in there." Like changing wheel bearings when the wheel is torn down.

Jim