Jay, thanks for the clarification and photos. I wonder if I could get a competent and bored machinist to make me up a set like that?
Dana: I'm in Crestone, down in the Sangre de Cristo Mountains just north of the sand dunes.
Bob Herman - 3/23/2016 3:40 PM Jay, thanks for the clarification and photos. I wonder if I could get a competent and bored machinist to make me up a set like that? Dana: I'm in Crestone, down in the Sangre de Cristo Mountains just north of the sand dunes.
Bob,
IF Jay would release the drawing on the triple tree extension, I can turn you to a great machinist and Guzzi Guy in South Dakota.
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Jay,
That is a great idea...
Best,
Rob
Thanks, Rob. It so happens I know a machinist here in Colorado who recently lightened a Guzzi flywheel for me, and I would be happy to bring him a project like this.
Jay: I like the simplicity of this idea. Two questions:
-Structurally, has this modification proven up to the stresses of long term use?
-Is there an inherent advantage or disadvantage to moving the fork legs forward without increasing rake?
Thanks for sharing your knowledge, I really appreciate it.
Bob
This set up works fine and has held up long term. As a clarification. Even with triple tree's we are not changing the "rake" it may look like we are but we are not. To change rake the angle of the head stock on the bike would need to be changed. All we are doing is reducing trail. To reduce trail very much over simplified all you need do is move the front wheel forward. In the case of the clamps we do this by moving the entire fork assembly. I do not have drawings on this. It has been a very long time since we built these and we had a flood a dozen years ago that wiped out our hard drive and the drive that was backing it up. No idea why we still have this photo which was taken sitting on the hot tub of my old house which we worked out of back in 1998-1999 time frame. Figuring it out is not all that hard, you need to measure fork tube diameter, fork tube spacing and figure out how much you want to reduce trail by. In general most people like to have trail end up at about 2 inches although unless you live in the flat lands I like to go a bit more. If you bike now has 4 inches of trail and you want two inches then move the forks forward by 2 inches. A less expensive way to possibly make these rather then machining them from billet is to have them water jet cut at which point making one or making 100 there is not much difference in the machining cost just more material cost.
The reason we developed these is simply because they are cheaper then most other methods. We also did them for air head BMW's (my wife's R100S we dropped down to 1.2 inches of trail) and the GL1000
Jay G
DMC sidecars
www.dmcsidecars.com
866-638-1793
Thanks, Jay, for taking the time to explain all this. And sure: coming up with the dimensions is no problem. And a hot tub is a great place to mull over such things!
So, to clarify: when you modify triple clamps, you're moving the fork legs out but they are still at right angles to the the triples? So yeah, no change in rake.
Yes, no change to the angle at all which is why these should be able to be made by a really good water jet company. But again, even if we changed the angle of the forks in the clamps we would not be changing the rake! Rake is the angle of the head set not the angle of the forks.
Jay G
DMC sidecars
Gotcha.
