Extended Fork Bushes

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I'm bringing a 750 roadster back to the road and the threads on this forum have been hugely helpful. So first of all thank you! I will post a separate thread with a proper introduction but right now I'm stuck on the forks.

As part of the overhaul I'm renewing fork internals and decided to fit the RGM extended top bushes. The bushes are limiting travel, when the bottom bush gets in contact with the top bush, such that the damper road stays 1.5inches above yokes when the forks are fully extended. To fit the top cap the springs need to be compressed quite a bit which was not the case before. Rods are new Andover Norton items and same length as what was in before.

Does this sound right? Would anyone have experience on this?
 
As part of the overhaul I'm renewing fork internals and decided to fit the RGM extended top bushes. The bushes are limiting travel, when the bottom bush gets in contact with the top bush, such that the damper road stays 1.5inches above yokes when the forks are fully extended. To fit the top cap the springs need to be compressed quite a bit which was not the case before. Rods are new Andover Norton items and same length as what was in before.

Does this sound right?

No, something is wrong, as the extra length of the RGM bushes occupy what would previously have been an 'empty' space (except for oil) beween the upper and lower bushes.

The bushes are limiting travel, when the bottom bush gets in contact with the top bush,

Yes, the bushes would be expected to reduce the travel compared with the old bushes with the damper rods disconnected, as the damper assembly when connected reduces the overall fork travel by approximately 1.5 inches, so what is the fork travel?

Are you sure you don't have 'Covenant' sleeves fitted?
https://www.rgmnorton.co.uk/buy/covenant-fork-damper-conversion-kit-improves-damping_2294.htm

If both the Covenant sleeves and extended bushes are fitted then it would drastically reduce the fork travel.
 
Thanks L.A.B. No covenant sleeves fitted. I'm replacing all bushes, seals, damper rod, damper cap, etc.

In the meantime I went down to the shed and re-measured everything and believe found the culprit. The stanchions are shy of 22inch and commando stanchions should be 23.15inch.

Not sure what type of stanchions these are. Now, do I replace the stanchions? Or fit the shorter bushes?
 
In the meantime I went down to the shed and re-measured everything and believe found the culprit. The stanchions are shy of 22inch and commando stanchions should be 23.15inch.

Yes, they sound like 'short Roadholder' (Featherbed) stanchions. ;)



Not sure what type of stanchions these are. Now, do I replace the stanchions? Or fit the shorter bushes?

Your choice, but with the standard Commando rod and damper tube assembly, standard upper bushes and those shorter stanchions the springs will become coil-bound before the forks reach full compression.
 
We'll replace the stanchions then. Have already paid for new bushes, rods and the alloy damper tubes. Thanks again for the quick replies.
 
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