Custom Commando questions

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Well now, after quite a long search I've aquired a '71 750 Commando Roadster....not an easy task here in central Alaska. I would like to know any information about lowering the overall stance of this bike as it's going to be a custom job. I've seen this done on the Colorado Norton Works website and I really love the look..... hope this doesn't offend the puritist Norton owners :? Can anyone tell me what is involved in shortening the fork tubes and how short of a shock I can use without drasticly effecting road worthiness? Also I'll take any advise you experienced Norton wrench hounds may have since this is my first brit project.
 
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I know the owner of the lowered bike she is short and needed the changes to ride. The shock mounts were moved forward and the wheels were relaced with smaller rims. The forks can be shortened by re cutting the taper that locks into the upper triple tree "Forking by Frank" could do this for you. How much can be gained by moving the upper shock mount foward would determine how much to take from the forks. Of course you may need to find a shorter set of springs for the front end because just cutting them shorter would knock out their progressive workings. Remember that you're going to have to move up all things that drag when you turn so you're facing lots of custom brackets for foot pegs and controls. You may also need to custom bend the header pipes and redo a new iso system for the mufflers. You can't have an iso mounted engine and not have an iso mounted exhast system. As far as modifiying the bike seems everyone does it but taking away the Commando turn lean would be a crime so these changes won't be cheap. norbsa
 

Anonymous

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The Atlas fork tubes and rear shocks are both shorter than the Commando parts and can be used on the Commando without modification
 

Ron L

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I believe that stock fork springs are not progressive and shortening these may be appropriate. I find shortening the fork tubes by cutting the lower end is easier than cutting the taper and and re-threading. Any competent home machinist with a lathe that can handle the length should be able to do it. Cut to length, cut down the area for the bottom bush, cut a slot for the circlip, re-drill the cross holes.

I pick up new extended tubes for very cheap at swap meets and have them cut down to stock length. New tubes for $20!!
 
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Ron , I looked at this today and it looks like a horse a piece to me. Tappings real easy on the lathe and so is that short taper. Now finding the right tap could be fun that's why I came up with Forking buy Frank. You must have a Brideport in the garage as well. norbsa
 
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norbsa48503 said:
I know the owner of the lowered bike she is short and needed the changes to ride. The shock mounts were moved forward and the wheels were relaced with smaller rims. The forks can be shortened by re cutting the taper that locks into the upper triple tree "Forking by Frank" could do this for you. How much can be gained by moving the upper shock mount foward would determine how much to take from the forks.

I've been thinking about this. I have a MkIII and am interested in lowering the bike 1" - 1.5". In understanding this correctly, I have to alter the rear upper shock mounts (move them forward) on the frame or was that for older Commando frames since I believe the MkIII had different upper rear shock mounts.

I can't find a phone number for Forking by Frank either. I contacted them by e-mail around 2 months ago and have had no response.
 

L.A.B.

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Coco said:
I have a MkIII and am interested in lowering the bike 1" - 1.5". In understanding this correctly, I have to alter the rear upper shock mounts (move them forward) on the frame or was that for older Commando frames since I believe the MkIII had different upper rear shock mounts.

Not an easy job on the 850 MkIII as immediately forward of the L/H shock mounting position in the rear plate is a large hole that allows access to the MkIII seat hinge front mounting stud nut (if you look under the seat you will see this) and the stud or complete hinge would also need to be modified or removed to allow the shock to be mounted forward of its normal position (also the R/H seat lug would have to be moved but you may be considering a different seat anyway I think?) and the access hole welded, the lower edge of the mounting brackets curve upwards at either side of the standard mounting position, so it may also be necessary to remove some metal from the brackets so the top shock spring retainers do not hit the brackets as the suspension compresses.
It would seem a lot of unnecessary frame butchery when fitting slightly shorter shocks would give exactly the same result?
 
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L.A.B. said:
Coco said:
I have a MkIII and am interested in lowering the bike 1" - 1.5". In understanding this correctly, I have to alter the rear upper shock mounts (move them forward) on the frame or was that for older Commando frames since I believe the MkIII had different upper rear shock mounts.

Not an easy job on the 850 MkIII as immediately forward of the L/H shock mounting position in the rear plate is a large hole that allows access to the MkIII seat hinge front mounting stud nut (if you look under the seat you will see this) and the stud or complete hinge would also need to be modified or removed to allow the shock to be mounted forward of its normal position (also the R/H seat lug would have to be moved but you may be considering a different seat anyway I think?) and the access hole welded, the lower edge of the mounting brackets curve upwards at either side of the standard mounting position, so it may also be necessary to remove some metal from the brackets so the top shock spring retainers do not hit the brackets as the suspension compresses.
It would seem a lot of unnecessary frame butchery when fitting slightly shorter shocks would give exactly the same result?

Seems like a giant pain in the ass just to acheive a better looking stance. I am getting a different seat but I will forget the idea of lowering as it seems like a complete fabricating nightmare. Oh well, onto my next silly idea.
 
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