Thursday, March 29, 2012

Test ride with 24" front wheel.

This seems OK, the steering feels a little different to how I remember it, it is nearly a year since I last used this bike. It does not actively seek to turn left or right all by itself, but doesn't seem like riding no-hands would be very easy, it seems about neutral. It is certainly nothing like the 26" mountain bike wheel and forks I tried, then it immediately wanted to turn away from straight ahead.

Both handbrake levers were broken in the crash.

The front wheel axle is about 15mm higher off the ground than is the rear axle. This could be reduced by using a 1.5" tyre instead of the 1.95" now fitted. I even think the front mudguard might be persuaded to fit with a narrower tyre on the 24" wheel.

With the 26" wheel, it had excessive "wheel flop":

Wheel flop refers to steering behavior in which a bicycle or motorcycle tends to turn more than expected due to the front wheel "flopping" over when the handlebars are rotated. Wheel flop is caused by the lowering of the front end of a bicycle or motorcycle as the handlebars are rotated away from the "straight ahead" position. This lowering phenomenon occurs according to the following equation:
Because wheel flop involves the lowering of the front end of a bicycle or motorcycle, the force due to gravity will tend to cause handlebar rotation to continue with increasing rotational velocity and without additional rider input on the handlebars. Once the handlebars are turned, the rider needs to apply torque to the handlebars to bring them back to the straight ahead position and bring the front end of the bicycle or motorcycle back up to the original height.

Wednesday, March 28, 2012

Forks looking good.

I fine tuned the fork bending today, they seem OK. I think I will just put a bit of packing, 1 or 2mm or so, in above one axle to straighten the wheel a little, will hold off on any filing for the moment.

If I stick with this 24x1.95 knobby tyre, I will trim the outermost knobbly bits, they barely clear the forks and the wheel is not perfect, neither is the tyre.

I need to enlarge the holes for the rack to go over the axles, not much in it, they'll still have enough meat on them.

Monday, March 26, 2012

Fork repair

I've made a start at straightening the forks. I held various parts in a wood-working vice and bent carefully.

At present, the 24 x 1.95 tyre is about 4mm off-centre, the knobbly bits on one side hit the fork.

 The wheel also tilts to one side, the head stem tube does not follow the same line as the tyre tread centre.

And the top part, whatever it is called, is not perpendicular to the wheel.

I will do a few more adjustments, and see how it goes.  I see 24 x 1.5" slick tyres are available, they will be the go if this works out.

I needed to file the drop-outs a little wider to take the wheel axle.

Monday, March 5, 2012

Black racks and other bits and pieces

I saw this on Note the black seat pole clamp, black handlebar clamp, black racks. Is the bell black? The handlebars look different to most also, less swept back.