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Corse1
12th November 2011, 07:14
So I have just tried to adjust the comp damping on my Showa front forks. Its the type you access from the bottom through the Axle. One side is all good and the other doesn't stop clicking in either direction so there is no end to the adjustment. LH side has the correct range of 14 clicks soft to hard. The RH side clicks the same but has no end to it.

I have had the forks serviced and guy says he has not touched this part of the forks for oil and seal change. I tend to believe him. i am wondering if you can just pull the fork and turn upside down. then remove the adjuster unit for inspection.

And no I m not sure if it was working before service as the last time I adjusted them would have been 3 years ago probably but the adjuster was working fine then. They are the STD forks on a ST4s Ducati.

Any ideas????

Cheers in advance.

Robert Taylor
12th November 2011, 15:17
So I have just tried to adjust the comp damping on my Showa front forks. Its the type you access from the bottom through the Axle. One side is all good and the other doesn't stop clicking in either direction so there is no end to the adjustment. LH side has the correct range of 14 clicks soft to hard. The RH side clicks the same but has no end to it.

I have had the forks serviced and guy says he has not touched this part of the forks for oil and seal change. I tend to believe him. i am wondering if you can just pull the fork and turn upside down. then remove the adjuster unit for inspection.

And no I m not sure if it was working before service as the last time I adjusted them would have been 3 years ago probably but the adjuster was working fine then. They are the STD forks on a ST4s Ducati.

Any ideas????

Cheers in advance.

You can place the fork on its side in a vice but facing slightly downwards so that the orientation of that adjuster is uppermost. Then you can remove with no risk of oil loss. The detent mechanism is either broken or something else is and it will be readily apparent when you remove.

Clearly the forks were not properly tested for function and response range to adjustment when ''serviced''. A fundamental test.

Corse1
12th November 2011, 15:56
You can place the fork on its side in a vice but facing slightly downwards so that the orientation of that adjuster is uppermost. Then you can remove with no risk of oil loss. The detent mechanism is either broken or something else is and it will be readily apparent when you remove.

Clearly the forks were not properly tested for function and response range to adjustment when ''serviced''. A fundamental test.

Thanks Robert. When I picked up the forks I pushed each one through its travel independantly and I noticed one felt a bit different from the other. I thought oh well he is a well known service agent for suspension in the area and an ohlins approved agent so just put them on and forgot about it until I re-registered it. On his side though I have given him a call last week and he said to bring the forks in but I think he intimated it was nothing he touched but have to give him the benefit of the doubt. He would probably just look and advise from there and they are a great dealership so not really a problem with that apart from amybe he didn't carry out the test you describe. Of curse I could have damaged it trying to adjust it passed its end of adjustment and broken something but I don't think so.

I just thought I would have a look myself so I can understand what may have happened. thanks for the response and will pull it apart next week.

Corse1
30th November 2011, 17:01
You can place the fork on its side in a vice but facing slightly downwards so that the orientation of that adjuster is uppermost. Then you can remove with no risk of oil loss. The detent mechanism is either broken or something else is and it will be readily apparent when you remove


Ok Robert, Finally removed the fork just tried to remove the adjuster and once i had it moving the whole adjuster unit is spinning and not coming out of the fork. It feels like there is friction like an "O" ring but it is not unwinding like you would think and you cannot rotate clockwise to secure it again as it spins in both directions. It is not loose so it can rattle it just sits there and rotates with the socket seemingly forever in both directions.

The schematic I have (below) of the fork does not show any detail of the adjuster (15) and how it is retained in the fork. I thought it would just undo:facepalm:

Drew
30th November 2011, 17:18
Ok Robert, Finally removed the fork just tried to remove the adjuster and once i had it moving the whole adjuster unit is spinning and not coming out of the fork. It feels like there is friction like an "O" ring but it is not unwinding like you would think and you cannot rotate clockwise to secure it again as it spins in both directions. It is not loose so it can rattle it just sits there and rotates with the socket seemingly forever in both directions.

The schematic I have (below) of the fork does not show any detail of the adjuster (15) and how it is retained in the fork. I thought it would just undo:facepalm:Looks to me like the adjuster doubles to hold the fork inner to the bottom. Pull the fork to full adjustment to put pressure on the inner and it will undo.

And if that is the case, then the problem could very likely be caused by the service agent when he did the seals.

My comment is best taken with lots of salt though, as I am only forming this on a grainy picture, not looking at the real thing.

Corse1
30th November 2011, 18:22
Looks to me like the adjuster doubles to hold the fork inner to the bottom. Pull the fork to full adjustment to put pressure on the inner and it will undo.

And if that is the case, then the problem could very likely be caused by the service agent when he did the seals.

My comment is best taken with lots of salt though, as I am only forming this on a grainy picture, not looking at the real thing.

Cheers Drew, Will check that out..........

Robert Taylor
30th November 2011, 18:41
I concur with Deviant Drew, or at least as much as can be gleaned from the schematic.
Just this week we fixed some RMZ450 Motard forks that had been done by another road race suspension ''tuner''. One fork was noted as being 6mm longer than the other prior to disassembly and the adjustment range was poor. As we dissassembled we noted that the longer fork was because the lockbolt was engaged by only 3 threads on that side. Such poor attention to detail that could potentially injure someone is not good.

Drew
30th November 2011, 19:46
I concur with Deviant Drew, or at least as much as can be gleaned from the schematic.


Gizza jod then mister!

Robert Taylor
30th November 2011, 19:54
Gizza jod then mister!

Well you couldnt do any worse than the plonker whose work we are correcting at increasing frequency.................

Drew
30th November 2011, 20:02
Well you couldnt do any worse than the plonker whose work we are correcting at increasing frequency.................I accept your offer!

I figure with the bar set that low I should be in for a pay rise in no time at all.

Corse1
3rd December 2011, 08:49
I concur with Deviant Drew, or at least as much as can be gleaned from the schematic.
Just this week we fixed some RMZ450 Motard forks that had been done by another road race suspension ''tuner''. One fork was noted as being 6mm longer than the other prior to disassembly and the adjustment range was poor. As we dissassembled we noted that the longer fork was because the lockbolt was engaged by only 3 threads on that side. Such poor attention to detail that could potentially injure someone is not good.

If you mean fully extend the fork then its already in that state but no joy. I am going to have to take it back to shop where they will probably have to pull the fork apart to get the comp adjuster out for inspection.....bugger.

Drew
3rd December 2011, 13:15
If you mean fully extend the fork then its already in that state but no joy. I am going to have to take it back to shop where they will probably have to pull the fork apart to get the comp adjuster out for inspection.....bugger.

We mean pull the fork in the direction of full extension as you wind the bolt. Once the bolt starts to loosen there is nothing to stop the cartridge from spinning inside the tube. So by extending the fork it holds the cartridge down to stop it spinning.

To be honest, if this doesn't work, I suspect that the problem you originally noticed is a symptom of something a tad more severe.

I suggest you not take the fork back to the same service agent. Robert is very fair with his pricing, and a mongrel for wanting to one up other suspension techs who are not what they claim. Send it to him and his verdict will be one you can take to the bank, for less than what some might charge in bits you don't need.

Corse1
7th December 2011, 14:13
We mean pull the fork in the direction of full extension as you wind the bolt. Once the bolt starts to loosen there is nothing to stop the cartridge from spinning inside the tube. So by extending the fork it holds the cartridge down to stop it spinning.

To be honest, if this doesn't work, I suspect that the problem you originally noticed is a symptom of something a tad more severe.

I suggest you not take the fork back to the same service agent. Robert is very fair with his pricing, and a mongrel for wanting to one up other suspension techs who are not what they claim. Send it to him and his verdict will be one you can take to the bank, for less than what some might charge in bits you don't need.

Thanks Drew,

I did take the fork back to the same place and it appears that it may have been a small problem with the compression needle not sitting in the fork inner properly. I have been carefull not to name the tech as he has a very good reputation. It appears he did not check before handing the forks back but he would usually do this. Must have been a busy day. Anyway its all good now and have a learnt a little more about forks :yes:

Drew
7th December 2011, 19:18
Thanks Drew,

I did take the fork back to the same place and it appears that it may have been a small problem with the compression needle not sitting in the fork inner properly. I have been carefull not to name the tech as he has a very good reputation. It appears he did not check before handing the forks back but he would usually do this. Must have been a busy day. Anyway its all good now and have a learnt a little more about forks :yes:

Glad it worked out, and the tech put it right for ya.

I'm off to look up how those forks go together so I can figure out how it went wrong. It's gonna bug me otherwise.

Corse1
13th December 2011, 11:02
Glad it worked out, and the tech put it right for ya.

I'm off to look up how those forks go together so I can figure out how it went wrong. It's gonna bug me otherwise.

Did you find out Drew? After it has been pulled out we found the little piece that moves in and out with the clicker to control oil flow was not sitting in the clicker unit for some reason? When put back in and installed there is only a 10 click range of movement rather than the 14 it should have which is still a problem to resolve. it seems when putting the pieces back together the little piece can't be put back as far in as it should be. Like it bottoms out before it should in the adjuster.

Corse1
22nd December 2011, 14:06
After taking the parts and measuring them I confirmed that the parts were all seating in their home positions at either end of the stroke but still only 10 clicks.

SOLUTION: Add a 1mm copper washer to the adjuster and bingo back to 14 clicks. Still a mystery but it works fine now. Adjusters are exactly the same part as a 94 XR600 for maybe a cheaper solution for replacement...........