Joined Nov 2001
17K Posts | 774+
Ely, England
Just thought I'd try a thread about this era: the 2004-2008 MX and enduro machines.
Just want to break down the handling, balance and suspension of these years and how we make them handle better!
I'll start the ball rolling by saying that I've tried to work out what the factory thought was the best handling/sussie set-up on their bikes.
looks like a set of WP race forks and rear shock as the standard stuff wasn't up to much right? handling wise the factory appear to have gone to 17mm triple clamp/yokes and my recent tests show more weight going onto the front. the trouble is that to keep weight on the front by lowering the forks or jacking the rear: means that the rear shock is hard.
that in turn means that there's no transfer of weight to find grip on the rear and the other loss is that the bike doesn't point around the corner with a stiff spring but always outwards off the course!
looking at old tests and previous info here shows that the factory did two or three things for the rear.
they appear to have raised the engine at the front with new plates making the bottom line of the engine parallel to the bottom frame rails.
they have also raised the swingarm pivot point by 3mm by machining the frame and welding stepped collars in (perhaps) and putting 3mm 'above-centre' crankcase holes in so that the coutershaft sprocket is up say 3mm but that the swing-arm pivot has gone up another 3mm so that the sprocket to S/A pivot is the same but that the swing arm must surely point down now more steeply.
the pivot to shock point is 21cm and the distance to the wheel spindle we'll say is 60cm so the rear wheel has been forced down by 6mm or so.
In order to get the back to sit on acceleration leaving the corner I trust a softer spring would allow this and the droop at the back end is accounted for in some way by the 6mm? this should give good or better hook up and the better the hook up the more it would sink.
in the meantime over rollers etc the extended rear wheel well below the S/A point will force the wheel down for great drive? I suppose another way was to have a completely new top shock mount about 5-10mm lower and allow for the soft rear shock yet keep the same rear ride height.
what I cannot for the life of me understand is why the Husaberg riders wanted the headstock out 15mm and 25mm respectively? I have found the more weight on the front the better! I don't think that they used that extra material to steepen the head angle again as they did in 2004? the photos I have of TMenduro's 496 special and of the welding done clearly show the head stock was merely extended and that the rake didn't change.
I'm hoping all these years later that I can persuade him to show a full side on photo. I don't believe the one about the tyre touching the headers.
anyway, your thoughts?
regards
Taffy
Just want to break down the handling, balance and suspension of these years and how we make them handle better!
I'll start the ball rolling by saying that I've tried to work out what the factory thought was the best handling/sussie set-up on their bikes.
looks like a set of WP race forks and rear shock as the standard stuff wasn't up to much right? handling wise the factory appear to have gone to 17mm triple clamp/yokes and my recent tests show more weight going onto the front. the trouble is that to keep weight on the front by lowering the forks or jacking the rear: means that the rear shock is hard.
that in turn means that there's no transfer of weight to find grip on the rear and the other loss is that the bike doesn't point around the corner with a stiff spring but always outwards off the course!
looking at old tests and previous info here shows that the factory did two or three things for the rear.
they appear to have raised the engine at the front with new plates making the bottom line of the engine parallel to the bottom frame rails.
they have also raised the swingarm pivot point by 3mm by machining the frame and welding stepped collars in (perhaps) and putting 3mm 'above-centre' crankcase holes in so that the coutershaft sprocket is up say 3mm but that the swing-arm pivot has gone up another 3mm so that the sprocket to S/A pivot is the same but that the swing arm must surely point down now more steeply.
the pivot to shock point is 21cm and the distance to the wheel spindle we'll say is 60cm so the rear wheel has been forced down by 6mm or so.
In order to get the back to sit on acceleration leaving the corner I trust a softer spring would allow this and the droop at the back end is accounted for in some way by the 6mm? this should give good or better hook up and the better the hook up the more it would sink.
in the meantime over rollers etc the extended rear wheel well below the S/A point will force the wheel down for great drive? I suppose another way was to have a completely new top shock mount about 5-10mm lower and allow for the soft rear shock yet keep the same rear ride height.
what I cannot for the life of me understand is why the Husaberg riders wanted the headstock out 15mm and 25mm respectively? I have found the more weight on the front the better! I don't think that they used that extra material to steepen the head angle again as they did in 2004? the photos I have of TMenduro's 496 special and of the welding done clearly show the head stock was merely extended and that the rake didn't change.
I'm hoping all these years later that I can persuade him to show a full side on photo. I don't believe the one about the tyre touching the headers.
anyway, your thoughts?
regards
Taffy