Shorter Shock for Supermoto - FE501

bergryder

i'm not into SM but i did do RR for 14 years and one of the tricks for making bikes turn quicker was to have less offset at the triple clamps and also to drop the forks UP through the TC's and when the arse end stood up to try and lower the rear subframe with a re-weld!

it's been done here and i'm also thinking of doing it to mine. mikst has pictures of this in his gallery.

regards

Taffy

lower shock

I heard that you can use some kind of spacer on the interals of the shock which shortens the length. Hope that helps.
John

If you want it to turn better, you would not lower the rear. Raising the forks in the clamps and/or running less rear suspension sag will help it to turn better. As far as lowering the current trend is to not lower the bike unless you are vertically challenged. Lowering the bike will often cause peg dragging.

You need to elaborate a lot more on your set-up before appropriate advice can be given. Are you running 17's? What size tires and rims? Have you altered your suspension springs or valving from stock? Etc.

P.S. Some of the Pro SM racers are cutting the sub-frames at the lower mounts to lower them a bit, but this can only be done on dedicated bikes running 17's. MX wheels will not clear under full compression on many bikes with cut subframes. This mod is typically done for rider comfort.

not true powerfeind. i have cut out enough to drop the seat 3" on my old yamaha WR400 and i've already checked two years ago the space twixt underside of seat and top or rear tyre.

i used the simple method of a 1" strip of metal looped and bolted up to the underside of the seat bolt. the loop was over 3" tall and was untouched-though very muddy after some big MX jumps were taken by me ( a big fairy admittedly!).

the SM should have even more space.

regards

Taffy

Taffy said:

not true powerfeind. i have cut out enough to drop the seat 3" on my old yamaha WR400 and i've already checked two years ago the space twixt underside of seat and top or rear tyre.

Taffy

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Please reread what I wrote. I said many, I didn't say all wouldn't have clearance for lowering with MX wheels. And Yamaha's are known to be arse high. Cutting/lowering a subframe does not fix a poorly set-up chassis.

Re: Shorter Shock - FE501

BergRyder said:

The bike has a 17" front wheel with a 120/70 tire, and the stock 18" rear rim with a 130/80 tire. The problem isn't necessarily that the steering isn't quick enough, as the 17" tire took care of that. The bike from the apex of a corner and accelerating out, the back end seems high, harder to transition from side to side than it would if it were lower. It also feels like your going downhill even when accelerating out of a turn when I would like the rear to "squat down". When the bike is on the stand there is 14 1/4" of rear wheel clearance , 12 3/4" when the bike is standing on the floor, there is 2 1/2" of sag when I sit on it. I'm 5-11", 163 pounds if that helps.
The 95 FE501 has a huge rear fender (mudguard to you Brits) which accentuates the problem.

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With your current set-up I would imagine that the bike probably has terrible head shake also, unless you have the forks overly stiff.

The 18" rear set-up is a bit of a odd set-up and is probably causing many of your problems. With that tire and rim you are probably about an inch higher at the rear axle than a typical 160/60/17 tire. This is causing part of the high rear, and also shifting weight forward and not letting the bike squat. You should also be running more sag. 3-3.5" is more typical for motard, and will let the bike squat more.

To little squat and your bikes back tire will typically spin up after getting back on the power after you apex, and/or it is to easy to oversteer to the inside of the corner. If you are squating to much, the bike will want to run wide and you will have to fight it to stay on your choosen line.

To help determine your sag and correct rear spring rate follow the following guidlines(Substituting the 3-3.5" for the 4", possibly even the full 4" with that 18" rear.):
How To Set Your Race Sag
Use Static Sag To Determine If Your Rear Spring Rate Is Correct

Remember to keep spring rates balanced front and rear, if you alter them.

Your comp/reb valving will typically be slower on both for the fork from offroad, and the rear will be slower reb.(Running less sag in the rear will cause more/slower compression, but speed rebound). As a general rule, when bouncing up and down on the bike it should remain level front to rear when your weight is centered over the pegs.

And finally, try to find someone local that knows what they are doing(A SM racer) to help you. A road racer will probably set the bike up to stiff, and an MX guy will set it up to soft.

I know you said you didn't want to spend a whole lot to begin with and bergs have pretty good suspension for sm as standard(just a bit of tweeking)However due to the age of your bike, I can only presume it wasn't a factory sm therefore really does need to go into a suspension specialist for a personal makeover.Over here it costs about £200- £300 so I expect nearly double that in dollars but it will be the best dollars you have spent.
I would recommend getting the suspension done before ANY other go faster add ons, pound for pound(or dollar for dollar) its the best performance mod you can do