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#713746 11/03/17 8:45 pm
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I have a Norton P11 motor and transmission in a Trackmaster frame. It now has a set of forks from a Honda, unknown model. It has the adjustments on top of the fork tube. The tubes push through the top clamp and stick out about 2". I have enough room at full compression.
I would like to shorten them ...how to do this? Is it simply a matter of cutting off 2" from the tube, 2" from the spring, and 2" from the adjusting rod? What shop could advise me or do the work?

This is simply for appearance...I don't like seeing the extra tubes sticking out.

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A decent machinist could shorten the tubes (be aware they are hard chromed, so the non-moving top of the tube, where sharp edges won't be as serious, may be the best point of attack). The fork springs will be considerably stiffer if you shorten them, but that may be desirable. Not super familiar with damping adjusting rods, but since the adjustment happens deep in the internal damping mechanism, shortening it should work fine. Contact someone like RaceTech <http://www.racetech.com/> for definitive answers, and maybe more.

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I had the same question , with fitting some early Yamaha R6, to a Norton ??? when you consider the difference between long roadholder (Commando) and short on, the difference is between : tubes/stanchions ( logical!!), and damper tubes , the springs are the same (but the difference is not exactly2" as mentionned above!), and in my mind a shorter spring is not stiffer than a longer one (if the same rate and if they are free , as long as they do not get coil binded.........??), more thoughts will be wellcome ..........!

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A method of shortening rod damper forks I have used in the past is to shorten the springs (or spring spacers if fitted) and fit a spacer under the piston and top out spring. It is also totally reversible if you mis-measure


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put a spacer on the dampening rod; I would not recommend shortening the stanchions as they will create a stiffer front end with them further into the fork legs. Do't shorten the springs, either use racetech, progressive, etc, as these are usually shorter than stock anyway, and will retain the correct weight. A shortening a spring will make it stiffer.

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Sounds like a cool bike. Is it for street or track? I modified my Champion / Triumph track bike for street with Kawi forks I cut down.
It's a strait up job if you have the right equipment and tooling.


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The Suzuki DR650SE has that as an stock option to lower the bike, two mount holes in the rear linkage and the upper spacer (on top of the main spring) in the front forks can be moved to the area of the top out spring (As Andy says)
With that bike having around 10 inches of travel losing around 1-1/2 " isn't so bad to get the bike a little lower.

An easy mod for sure (if you have the tools to do it as a modification) but can you afford to lose 2 inches of fork travel, if they have around 6 inches to start then probably not a problem.
Are these forks damper rod forks or some form of cartridge although the same can be done with the latter.

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I have not pulled the forks apart and I am not sure what bike they came from. I will not know anything until I pull one apart and lay everything out on a table. I want to get some idea of what to do at that point. If there is a 1" spacer between the fork cap and the spring, and I remove it, then I lose 1" of travel? Not a big deal. will anything else happen.

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Just removing the spacer won't shorten travel, just decrease preload (if any). Why not post a pic of the forks to see if they can be identified?

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that tutorial was very good. In about 2 months I will get to the job. Right now (Tuesday) I am making a set of high pipes and then a center stand.

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Most of these forks that I have seen have a spacer between the spring and top nut. You can shorten the stanchions that much, take out the spacer and shorten the damper rod without much change to the fork action. They will be a little stiffer due to the lower air spring volume.


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