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two bike!! Q's
joolsmi16 - 27/8/09 at 10:16 PM

Hi all, have two bike issues:

First why do bikes have all the weight very heigh on the bike? i.e. rider, fuel tank etc..

Also think of turning my cbr600 into a streetfighter and want to fabricate my own tubular frame and transplant everyting else onto the new frame. I will need to get the bike through a MSVA and apply for a new VIN, but how can I get a age related number plate as I don't want a Q.

I'll have receipts for the steel to make the frame but I've had the bike for over a year and will have no receipts only the V5??

Thanks

Jools

Mark G - 27/8/09 at 10:28 PM

I think the rules for bikes are different for cars so you may want to try a bike specific forum. One thing that I think is cool is that on the Buell's to keep the center of gravity lower the fuel is not in a tank but is in the frame. Apparantly the box where the fuel tank normally would be is the air filter housing?!

[Edited on 27/8/09 by Mark G]

Rod Ends - 27/8/09 at 10:29 PM

Inertia - the way it's (nearly) always been done.
Motorbikes evolved from bicycles.
Search for Feet Forward motorbikes.
Also see recumbent bicycles.

Chippy - 27/8/09 at 10:29 PM

I know a guy who builds "special" bikes, he just uses the original headstock with the frame number stamped on it to get it registered as the same age. HTH Ray

blakep82 - 27/8/09 at 10:31 PM

quote:
Originally posted by Chippy
I know a guy who builds "special" bikes, he just uses the original headstock with the frame number stamped on it to get it registered as the same age. HTH Ray


if someone did that with a car though, there'd be all sorts of things said on here

daviep - 28/8/09 at 07:01 AM

Building a bike frame requires a very accurate jig to ensure the headstock and swinging arm pivot are absolutely square.

Regards
Davie

Cousin Cleotis - 28/8/09 at 10:52 AM

To steer a bike the bottom of the bike has to move from under to top to make it lean, this is done by steering the opposite way to the corner. Imagine balancing a broom on your hand with the brush at the top, to go right you move the bottom of the broom left, then follow it to the right.

So keeping the bottom of the bike light is will turn in quicker.

Everyone steers a bike in the same way, we learn this when we first learn to ride a bike, and do it without thinking aver since.

Paul

sucksqueezebangblow - 28/8/09 at 11:33 AM

quote:
Originally posted by joolsmi16
Why do bikes have all the weight very heigh on the bike? i.e. rider, fuel tank etc..


The height of the weight of a bike is not as critical as on a car because the bike leans in corners. Thus there are no issues of roll centre and height C of G in corners. Height of C of G does of course effect dive and squat under breaking and acceleration so you would not want the weight any higher than it has to be but lean angles (i.e peg height) are more of a priority. How far forward or back the C of G is is perhaps more important and mass centralisation helps ensure the g load is shared evenly across both wheels in more conditions (breaking, accelerating, cornering etc.)