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coyote killer
10-17-2005, 02:55 AM
Which is better for sliding around fast corners??? A steep head angle or a shallower angle???

Did the 83/84 R's have a steeper or shallower angle than the 81/82 R's???

Now for a practical question....

Would setting the preload on the rear shock of my 81 R so that it rides as high as possible improve its sliding characteristics or should I try to lower the back end???

Huffa
10-17-2005, 05:57 AM
Which is better for sliding around fast corners??? A steep head angle or a shallower angle???

Did the 83/84 R's have a steeper or shallower angle than the 81/82 R's???

Now for a practical question....

Would setting the preload on the rear shock of my 81 R so that it rides as high as possible improve its sliding characteristics or should I try to lower the back end???

I'd have to say a shallower rake. Steeper will make it twitchier and not hold the slide as easy.

Setting preload all the way up puts more weight on the front end so if your getting too much bite now it may help. Also, if you run your chain as far back as possible (add a 1/2 or whole link) that's increasing the wheel base which will again make it more of a controlled slide but will also put more down force on the rear.

CoeShow
10-17-2005, 09:58 PM
coyote killer,

There is a clear balance that needs to adjusted according to track conditions AND rider ability for allowing your 3 wheeler to handle slides to your satisfaction.

When smaller circumference than OEM tires are mounted in the rear, the steering geometry (rake or caster) is increased. This change in steering will cause the trike to steer slower, and make the handlebars seem heavier when turning.

Most "flat track" tires are just that. Flat. They also typically have a much stiffer sidewall than OEM knobbies, and the change of tires will automatically aid in the trikes sliding ability.

The best solution is to lower the front end the same amount as the rear was lowered to balance it out. This can be done in a few different ways.

The 81-82 250Rs fork angle is different than the the 83-on angle (steeper). The later model 3 wheelers had additional caster built into the triple clamps. This allowed the trike to have increased hi-speed straight line stability while still offering lighter steering effort. It was a combination geometry.

Still, steering angle has little to do with "sliding ability". The best handling 250R that I ever raced for flat tracking duty was one that I had installed a 350X front end on. The 350X did not use the increased angle triple clamps.

The steering geometry is more noticable as far as steering "effort" and power needed to turn the trike while sliding or not.

Tire selection, weight transfer, and overall ride height are key factors. If you lower the machine too much, it will slide even easier, but will also loose traction needed for forward acceleration.

Thats why a "balance" is necessary to obtain the best handling charachteristics for the needs at the track. Its very similar to any dirt track racing. Set-up is key.

Mike

Tecate performance
10-18-2005, 02:12 AM
CoeShow, what are the reasons honda used a trailing axle on the 250r and leading on the 350x forks?

coyote killer
10-18-2005, 05:06 AM
Perhaps I should clarify that right now I am getting far too much traction at the rear end to slide more than just a little. The rear shock preload is low and the rear end sags when I sit on it. What can be done that will help it break free and slide???

coyote killer
10-22-2005, 04:42 AM
Anyone have a clue??

xljimmy
10-22-2005, 09:30 AM
What kind of tires do you have?

coyote killer
10-22-2005, 09:34 AM
Carlisle knobbys....They're similar to the balloon tires that came on it but much heavier...