scrapeing and grinding

Just installed a pair of dampers without the internal springs and they are very smooth , silent with no issues.
Put the springs in and ....OMG! grinding and rubbing , i would never use the stock internal springs on my forth coming special, The matters are compounded by the lousy internal finish, takes 2kg on scales to move them when fully compressed.
Ok been here before...its like a cold sore ..just keeps coming back :!:

Just come off the phone, a guy reports one damper leans over in the Commando slider, the retaining bolt hole is off set, he is going the rat tail the hole back into the center ..British again at its best :lol:

I couldnt agree more. I took apart an early front set recently and the edges of the springs were clearly worn but only in some areas.
And the metal dust was down in the bottom of the oil.
When you put the springs in and run down the nut on the top, the springs snake their way along. Previously I asked if there was
sleeve you could put them in. Is there? And is there a better internal spring on offer anywhere?

The best springs are for internal use ; multi stacked 80mm long springs with nylon connectors , 5 per side at £8 each . made a few, the connectors being oilon make for smooth use. Not a new idea.. but stops the buckling . and no grinding!

John
I,m interested in your technique of using multiple springs & guide spacers to get round the snaking and grinding. This would enable you to easily create a progressive fork spring action if it was so desired. Easy to alter and tune. What are the dimensions and poundage of the springs and oilon connectors required for a normal fork action? How do you deal with the internal finish of the stanchions? Honing? Something as long and narrow as a stanchion could raise problems doing this (thinking again, maybe not as you can work from both ends)
As always you give me loads to think about!
Regards
Peter

Stacking springs is a good upgrade as can mix and match progressive to suit sag level and road conditions. I found out hard way some substitute fork fluids like brake fluid have nil rust protection so can bind forks after a season of storage. I used long rod with sand paper wrap to clean up stansions ID and wire brushed springs clean back to normal nil restriction.

The springs are stainless 4mm wire ID 16mm OD 24mm x 80 long 9,5 coils .closed and ground..they are stock from spring masters in Reddich .
When 5 are connected with Nylon spacers 8mm wide they produce a stack that as a complex rate due to all the closed ends .
I had to screw the springs onto a 16mm mandrill and machine them into a "D" profile ..the customer wanted a rate of 30 lbs /inch .. took lot's of trial's ,but he reported a 100% improvement to his forks, which where commando in a 500 Tri daytona ..
As the "stack" is stable and buckle reduced 80% the nylon [oilon] as very little pressure against the stanchion wall.
Not cheap or easy to produce..took me a week! as hobit says the stack as a progressive rate due to the 10 closed ends.. My spring maker was unable to give rate figures.

Use velocette stanchions [they make good stuff} the bore is good. Unlike the rubbish Indian stuff for £50!

dobba99 said:

John
I,m interested in your technique of using multiple springs & guide spacers to get round the snaking and grinding. This would enable you to easily create a progressive fork spring action if it was so desired. Easy to alter and tune. What are the dimensions and poundage of the springs and oilon connectors required for a normal fork action? How do you deal with the internal finish of the stanchions? Honing? Something as long and narrow as a stanchion could raise problems doing this (thinking again, maybe not as you can work from both ends)
As always you give me loads to think about!
Regards
Peter

Click to expand...

john robert bould said:

The springs are stainless 4mm wire ID 16mm OD 24mm x 80 long 9,5 coils .closed and ground..they are stock from spring masters in Reddich .
When 5 are connected with Nylon spacers 8mm wide they produce a stack that as a complex rate due to all the closed ends .
I had to screw the springs onto a 16mm mandrill and machine them into a "D" profile ..the customer wanted a rate of 30 lbs /inch .. took lot's of trial's ,but he reported a 100% improvement to his forks, which where commando in a 500 Tri daytona ..
As the "stack" is stable and buckle reduced 80% the nylon [oilon] as very little pressure against the stanchion wall.
Not cheap or easy to produce..took me a week! as hobit says the stack as a progressive rate due to the 10 closed ends.. My spring maker was unable to give rate figures.

Use velocette stanchions [they make good stuff} the bore is good. Unlike the rubbish Indian stuff for £50!

dobba99 said:

John
I,m interested in your technique of using multiple springs & guide spacers to get round the snaking and grinding. This would enable you to easily create a progressive fork spring action if it was so desired. Easy to alter and tune. What are the dimensions and poundage of the springs and oilon connectors required for a normal fork action? How do you deal with the internal finish of the stanchions? Honing? Something as long and narrow as a stanchion could raise problems doing this (thinking again, maybe not as you can work from both ends)
As always you give me loads to think about!
Regards
Peter

Click to expand...

Click to expand...

Would the nylon [oilon] get hammered when “coil bound” is reached? I like the idea but would like to know the life expectancy for the nylon spacers.
Regards,
Thomas
CNN

Ludwig
You posted just before I did. I like your idea there. What keeps them from floating?
Cheers,
Thomas
CNN

Beautiful sleek inspiring spring upgrades to view John and Ludwig, thanx for showing how the better half lives. Just in case ya misunderstand my statement, progressive spring rate is only gotten by mix of different rate &or length springs - Not by stacking same lengths of constant coil wound one rate springs. My meager experience only needs/benefits by Very Hi rate rate of valve spring almost coil bound for last 1/2- 3/4" or of travel extremes. I shudder to reflect on the conditions that the extra slick motion mods can be detected so leave that for others to benefit from.

Still scratching head on low oil level to eliminate air spring pocket effect and maybe leave rebound function starved for oil flow.

Any spring that is closed and ground becomes a progressive ,because the closed ends are weakest,they close faster .as my stack of 5 as 10 closed coils they compress before the rest. Giving a soft start. In normal Norton springs this effect is not noticed,due to the small percentage of the closed ends.

hobot said:

Beautiful sleek inspiring spring upgrades to view John and Ludwig, thanx for showing how the better half lives. Just in case ya misunderstand my statement, progressive spring rate is only gotten by mix of different rate &or length springs - Not by stacking same lengths of constant coil wound one rate springs. My meager experience only needs/benefits by Very Hi rate rate of valve spring almost coil bound for last 1/2- 3/4" or of travel extremes. I shudder to reflect on the conditions that the extra slick motion mods can be detected so leave that for others to benefit from.

Still scratching head on low oil level to eliminate air spring pocket effect and maybe leave rebound function starved for oil flow.

Click to expand...

Ok john that's makes sense how you got progressiveness in stack of same springs > their handful of slightly weaker thinned ends of springs would be similar to 1 weaker spring section with similar travel before coil bound. Its been 8+ yr since I was into SuVee's650 forks and getting annoying-dangerous stick-dive on braking this year so suspect spring rust but so low on priority may be a few more years rusting.

Stacked springs are great to create really progressive springs , but you need an internal spacer to lock up one of the composing springs. This way you can make a precicely defined cross over point .

Click to expand...

Ludwig could you expand on above internal spacer lock up feature? Does this only apply to spring expanding in tension or also compression?