Boxerworks.com

Generally it's the needle jet that wears more than the needle. I'm on 22,000 miles on the same jet. I think 30,000 is considered time to change. Needle jets are hard to measure for wear. There is only 0.02mm or 0.8 thou difference between the next size up of jet so that's probably the amount of wear...

the internal damping mechanism was changed quite significantly (and not for the better) to a design that was first use in R45/R65's in 1978. What's the deal with the "knurled nut" .. photos show they are internally threaded, but the front hub is not. Are there just smooth, press fit ones ...

I use the dipstick out of my car to check fork oil level. I find it's easier to see the clean oil level on the flat hatched portion of a proper dip stick than it is on a welding rod.

It's usual for any oil change to always remove the filler plug first. Haynes may be thinking that to leave the filler plugs in helps the pumping action to compress air inside the forks and expel the oil. But to replace the drain plugs before removing the filler plugs is nonsense.

1980 should make it the older design which I'm not familiar with. The best explanation of these earlier forks and the post 81 design is probably this:

http://www.vintage-register.co.uk/libra ... 0Forks.pdf

Hydraulic lock is hard to envisage due to the compression damping as the holes in the damper rod are quite large, certainly too large to get blocked by sediment. The rebound damping oil hole is much smaller and together with the damper valve is a more likely culprit. Is it a given that you are filli...

The thing most likely to prevent the forks rebounding against spring pressure is stiction due to misalignment. I suppose hydraulic lock could do that as well but I can't envisage how that could happen. Draining the oil would soon eliminate it as a possibility. I would remove the wheel and spindle th...

I think you may be thinking of the Monolever forks there, i.e. when the axles were moved to the bottom of the slider, instead of using a leading axle, and the 18" wheel. I wasn't thinking of the mono forks or anything to do with the axle. By the same in principle I meant the damping mechanism....

The 'W' rating of fork oil is not actually very helpful, except in general terms. It describes the viscosity of a given oil at 0 degrees c and has little bearing on the performance at any other temperature. BMW recommended specific oils for forks varying between 2.5W and 10W with many that didn't q...

Reassembling the fuel tap can be quite challenging to put it mildly and it can seem near impossible without devising some sort of jig to compress the assembly. It's one of those frustrating jobs where if you struggle, then it's best to walk away from it for a while and think of a solution. I can eas...