Originally Posted by TomTom
Taff, its hard to put words on riding impressions as you know.
What puzzles me slightly is by putting the bike more on its nose I should now have less trail, shorter wheel base, steeper fork angle, yes?
In my mind it then should be more prone to head shaking and more nervous, but on the contrary the feeling is like it now has more trail with a distinct planted feel to it and the force required to push the bars increased a bit (which I like).
What is that hinged feeling? Can you evolve a bit pls and Ill try answering that.
I don't think the bike is more on its nose by much anyway? I think unless you measured up to a point at the front with you sat on it before and after and did the same at the rear, that you can't be sure. i have said this here or nearby on UHE recently to someone? you have to have measured up to for instance a TC bolt head and to the rear tail pan before and after.
at most the front has dipped very, very slightly. wheelbase is the least affected and should be discounted in this instance.
the trail has changed at most and you lost 1mm in trail. but you added between 4 and 6mm depending whether you were on 18s or 20s before you started.
steering is changed for 2-3 reasons and one of them that blighted me in my last year of racing (2013) at the old age then of 53 was the sheer phuqin weight of turning and flicking the bike! but with spikes I'm guessing that it feels the same as 3 bar(75LB) in the tyre right?
so you don't feel heavy steering - just he-v-ie-r steering which is probably still great!
if you are throwing the bike onto opposite lock then you are not 'laying the bike onto its side' whereas if I look at Ice Speedway, those boys are as low as you can go. like that trail is critical.
if your slush ever becomes real ice, you use 1"/25mm spikes and you have your elbow down: what is stopping your steering turning straight to the side and facing the ice? nothing!
let's say you have a tea trolley OK with steering wheels AT THE FRONT? you remove everything and lay the trolley over just 10d onto the two left side wheels OK?
what happens to the front wheel? it turns 90d left...nasty! the whole idea with steering normally is that as you peel into the corner, the wheel always wanted to face 'that way'.
we get a lot of FS650e's in and they are running the same 22mm offset TCs as the dirtbikes. as you go to peel in to the corner the wheels are the equivelant of under the pivot on the tea trolley, they don't turn 'in', they point straight ahead so owners push onto the top bar, pull on the bottom bar and it goes around the corner. 18s - even 20s would cure this but do they change their bikes? nope!
so if as you peel in on a really cold day and you have real ice and as you lay it over the bike tries to ride through the inside of the corner then you know what the problem is!
it must be natural! that is why I think 14s are too much! I think when you lay it over it will want to go through the inside of the corner, it will oversteer like they say in car parlaince.
the hinged in the middle feel comes more in roadracing where you open the throttle from a hairpin and the steering gets straightened by the rear wheel, this could also happen to you. too much trail.....
when you wer a kid and you had to push the bicycle from the seat at the rear, the steering would be twisted but when you pushed the seat the front wheel straightened. same here, too much trail, open the throttle, steering straightens. you can only feel this effect at a slow corner where the steering is fully turned/turning.
the more trail you have, the more stable and you had acceptable trail before and have now added 5mm! so it is even more stable!! a steeper headstock is overruled by 'TRAIL' and TRAIL is the number 1 rule! speedway bikes are unstable NOT because of their headstock angle but because of the small amount of trail they choose to run. it is their choice!
usually we reduce the trail for lighter steering and to stop it 'dropping in' and the 'hinged in the middle' feeling when we open the throttle! you will decide how it is...
some ideas for you!