Honda SP2 Carbon Wheels - Do I need a steering damper...
Discussion
ks?Just had another thought, I think it could depend on which period of the wobbe we are talking about. I think a lighter wheel can make it easier to lose stability pre-wobble. However having a heavier wheel during the wobble could be worse as at this point surely it's the rotational mass of the wheel continuing the wobble?
In all reality your guess is probably as good as mine...
In all reality your guess is probably as good as mine...
Theoretically with less inertia it should give the suspension less of a hard time but in my hard of thinking head I can picture it being more flighty.
Either way I think you'd need to make some adjustments to suit.
Steve bass if he's still on here is your man.
I have been of no use as usual, you can thank me later.
Either way I think you'd need to make some adjustments to suit.
Steve bass if he's still on here is your man.
I have been of no use as usual, you can thank me later.
oh like mine 
I used one of these
https://www.scottsonline.com/ShopYourBike_Products...
I used one of these
https://www.scottsonline.com/ShopYourBike_Products...
Edited by Phud on Wednesday 7th March 09:09
knitware said:
Steve Bass, care to elaborate?
The bike has Ohlin forks which sit further up the clamps, lowering the bike at the front and has a Kyle link Ohlins rear that raises the rear so isn't a standard SP2 set up.
Front end wobbles are a product of fork flex and front end geometry. The bike has Ohlin forks which sit further up the clamps, lowering the bike at the front and has a Kyle link Ohlins rear that raises the rear so isn't a standard SP2 set up.
Wheels don't in themselves cause a wobble but their weight and inertia will maintain the oscillation and may even increase it as speed goes up.
Light weight wheels, being lighter have far less inertia than standard especially so in terms of rotational mass which is far more important than a static weight.
So when a fork has a lighter wheel attached it needs to be adjusted for the change in inertia as the wheel will move faster and take less effort to stop after its deflection.
So a simple rule of thumb is to open/reduce the compression and turn in/slow the rebound. A bit. A small bit. Depending on how much adjustment you have, probably no more than 10% in each case.
Regarding speed wobbles, as said above, geometry has a huge effect. You state the bike is lowered at the front and raised at the rear. This in effect reduces the rake which is rarely a good thing if you don't know the values you're starting with.
If the intention was to quicken the steering, it will but with some nasty side effects. Speed wobbles, front tucking, loss or reduced grip at lean are all caused by this.
I would recommend you lift the front of the bike back up which will bring the front back into shape. If you can bring it up beyond standard to level it off with the rear jacking in place this may be beneficial as a higher bike turns quicker due to a higher CoG. Effectively it want to fall over faster. And if anyone thinks raising the rear or dropping the front affects the weight distribution, think again. The only way to change that is to change the positions of mass between the axles. So a longer swingarm effectively moves the engine forward in the wheelbase and weight distribution is changed. All jacking or lowering does if done more than a few mm is negatively affect the basic geometry of the bike.
Another little check is to hold the front static and slowly release the clutch with the bike in gear. If the rear rises up then whats happening is under acceleration the rear lifts reducing the rake even further. This reduces trail and also makes the forks deflect backwards when the wheel is following the road rather than sliding up and down. The moment the energy stored in the deflected fork is released, the fork springs forward and you have the beginning of an oscillation moment. With continual energy inputs it'll maintain of get more pronounced.
When changing the rake, you MUST change the fork offset /trail to compensate. On bikes you can't make a single change without affecting other values that must be compensated for.
Looking at the first picture, i'd say you should consider pushing the forks through around 10mm to start with and go from there. Whilst it may look race bike like, pukka race bikes use a very different fork system which is why they have so much fork leg protruding above the yoke. You don't, so don't
BTW, that's a beauty....
Edited by Steve Bass on Wednesday 7th March 14:23
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