Landracing Forum

Tech Information => Technical Discussion => Topic started by: Sequim Jim on February 18, 2018, 09:57:17 AM

Title: Altered frame rules
Post by: Sequim Jim on February 18, 2018, 09:57:17 AM

Hi,
I'm building a BMW R100RT (airhead) to race in the APS-PF class. The frame is my own design, along with the chain drive conversion. Do I need to have the frame pre-inspected before Bonneville? I probably will not bring the bike I rode last year. Do I keep the same racing number or do I need to have another number assigned to my new bike?

Title: Re: Altered frame rules
Post by: Stainless1 on February 18, 2018, 10:34:07 AM

SCTA or AMA
If SCTA you will need a new log book and frame sticker... Your number is yours, not the vehicle's.

Title: Re: Altered frame rules
Post by: donpearsall on February 18, 2018, 12:31:01 PM

I have built bodywork similar to what you have drawn. I just wanted to compliment you on your sketching skills!
Also, make sure you can see straight ahead. You may have to raise your head a bit more.

Don

Title: Re: Altered frame rules
Post by: Sequim Jim on February 19, 2018, 09:27:22 AM

Thanks everybody!
One of my friends sent an email telling me the same thing. I was considering bringing two bikes but he said it's a lot of work, so I will have to decide whuch bike to going to Utah this year.
The BMW has been slightly changed and I'm having problems getting parts from Germany, so we'll see how things go.

Title: Re: Altered frame rules
Post by: wobblywalrus on February 19, 2018, 10:12:49 AM

It looks like it would be a lot more comfortable if the knees are moved back behind the cyl heads.

Title: Re: Altered frame rules
Post by: bones on February 19, 2018, 05:36:34 PM

I have been helping a mate here in Australia with an air head BMW for the same class.
It looks like you have taken a chain off the diff to the rear wheel. Unfortunately a lot of HP is used in the diff.
My mate has turned the engine 90* and used a TT Industries Norton box with a belt primary.
Turning the engine has not helped the width but it is a more efficient drive train.
Last year at Gairdner he ran a very easy 135.
We will see how it goes in a few weeks.

Like Wobbly said-- If you could move your foot rests back and also your seat, you may be able
to flatten your back, better aero,
I will get a picture and see how I go loading it.


cheers     Bones

Title: Re: Altered frame rules
Post by: grumm441 on February 22, 2018, 04:21:39 PM

Quote from: bones on February 19, 2018, 05:36:34 PM

It looks like you have taken a chain off the diff to the rear wheel. Unfortunately a lot of HP is used in the diff.


cheers     Bones

There's no differential in there
It's a final drive
G