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Front suspension 1970 R75/5 - its choppy over bumps

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bombard4101
Posts: 11
Joined: Fri Oct 27, 2006 3:00 am

Front suspension 1970 R75/5 - its choppy over bumps

Post by bombard4101 »

If you are talking about a "hole" down in the fork, as in an empty fork tube, you are missing a fork spring. From your description, that's all I can come up with. Sounds like it's time for a fork rebuild, because you can't tell what other bits and pieces might be missing from one side to the other.

magnetic
Posts: 11
Joined: Mon Apr 02, 2007 9:24 pm

Front suspension 1970 R75/5 - its choppy over bumps

Post by magnetic »

I was like a deer caught in the headlights -

The "Hole"/Missing spring was the actual fill valve that holds down the spring, one side came up with the cap.

The springs are with in specs, and I changed the fork oil(measured and everything. But the slap is still there. The sliders are in perfect shape, that is they move freely without catching.

If I have to rebuild the forks its going to be this winter, no way I'm missing another weekend of this weather.

Perhaps I can find an "expert" to give it a ride around and "feal" what the problem is.

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schrader7032
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Front suspension 1970 R75/5 - its choppy over bumps

Post by schrader7032 »

Where are you located? Maybe someone knows an "expert" near you...

Kurt in S.A.
Kurt in S.A.
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magnetic
Posts: 11
Joined: Mon Apr 02, 2007 9:24 pm

Front suspension 1970 R75/5 - its choppy over bumps

Post by magnetic »

I live in Napa, Valley. Evidently the closed airhead expert is in Santa Rosa, Michael I believe. It's not unridable, it just feels so odd, I have never felt a fork like this, granted I don't really know what this bike should feel like, but this certainly can't be it.

Thanks for your input schrader, I appreciate it.


Thankfully the engine/ carbs timing/ is flawless, except that Rocker arm slap, that you hear on so many /5's. Though I did find the bike a little sluggish after cleaning "restoring" the bars/lever mechanisms. I guess I had better look into re-synching the carbs, as I may have got something out of wack with the throttle cable.

Again thanks for everything.

magnetic
Posts: 11
Joined: Mon Apr 02, 2007 9:24 pm

Front suspension 1970 R75/5 - its choppy over bumps

Post by magnetic »

Well the problem was manifold. First the bumpers and rubber rings were bad. I serviced the forks and it greatly improved but there was still a problem. It turned out that there was play in the steering head, once that was repacked, adjusted and tighted the performance is very good. I still may change from 5w to 10w hydro oil, as it is hot here and I think that the dampening suffers a little from that with the light oil.

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VBMWMO
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Front suspension 1970 R75/5 - its choppy over bumps

Post by VBMWMO »

I get a "spring slap" over bumps. I dismantled the bars and all the levers for a cleaning and some paint touchup. But when I went to remove the forks, I found that one fork has a spring, and the other just has a hole. This is very confusing. Is this the standard configuration?
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