Building a race bike

sfcpiet said:
(3.412 x 43.2?) x 63 x 2 = 813500.982mm? = 813.5cm?

Didn't you pay attention at skool, Chris?

piet :D

Whot youse sain :-*
I hated school, all l could think of was getting out and riding motorbikes and girls.
Mathematics was not mr strong suit, there was 2 times I got kicked out of class:
I told the teacher:
l didn't care
Then, why should l care
And then why should l care

45 years later l now realise that that was 3 times, but why should l care?
 
chrisk said:
Whot youse sain :-*
I hated school, all l could think of was getting out and riding motorbikes and girls.
Mathematics was not mr strong suit, there was 2 times I got kicked out of class:
I told the teacher:
l didn't care
Then, why should l care
And then why should l care

45 years later l now realise that that was 3 times, but why should l care?

All I know is both you and Piet do nice work and I enjoy reading your posts.  Couldn't give a flying f**k about your school grades, it is the end product that counts - as in, how good your chosen work is and what sort of bloke you are...

Yogi
 
Dellortoman said:
Seems you didn't pay attention either Piet.

Half of 87 isn't 43.2 and you seem to have stuffed up your arithmetic. I dunno how you got 813, it's 749cc

Sorry Cam,

Had  a hard day and it was late...

Maths wasn't my strong point either, but at least I know how to get there. :D  For you buggers, I have to concentrate on using the . instead of the , as the decimal point.  3.142 is what I usually use for pi, close enough for my applications.

So; (3.142 x 43.5?) x 63 x 2 = 749126.637mm?    749cm?

Do I pass now? :D

piet
 
sfcpiet said:
Sorry Cam,

Had  a hard day and it was late...

Maths wasn't my strong point either, but at least I know how to get there. :D  For you buggers, I have to concentrate on using the . instead of the , as the decimal point.  3.142 is what I usually use for pi, close enough for my applications.

So; (3.142 x 43.5?) x 63 x 2 = 749126.637mm?    749cm?

Do I pass now? :D

piet

Yep, go to the top of the class, will meet you down the back of the oval at lunchtime and share a smoke....... If I ever get out of detention.
 
chrisk said:
Yep, go to the top of the class, will meet you down the back of the oval at lunchtime and share a smoke....... If I ever get out of detention.

Only "safe" places for a fag back then were back of the bike shed or behind the tennis court. :D

piet
 
Correct  :D

750cc class racing, sounds like fun and I like the idea of a challenge to see what can be done with a Laverda SF motor.
In theory it should be safe to about 11k,  If I can get it to rev that high in the first place.
Hope it will stay together  :LOL:

J
 
Having some bits made, anyone interested in the following.

Primary drive large sprocket, for Twin chains,  7075-T6 Aly Hard Anodised,
Cam drive sprocket, for Single chain, 7075-T6 Aly Hard anodised,

And later,
5/8 x 1/4  (520) front and rear sprockets in 7075-T6 Hard anodised. 
Will make a few diferent sizes but probably a bit odd for everything other than my bike due to rev range, I think I will need about a 50T rear sprocket if we get 11k revs

Prices will obviously depend on quantity and interest.

Regards,
Julian
 
Hi Folkes,

Frame and swingarm just arrived and is absolutely perfect!!!

Top welding and top workmanship, really pleased with it.
Pictures to follow tonight bit it's worth waiting for  :LOL:

Julian
 
Sorry for the delay, manic at work.

Some Quick pics, top one while it was still with JLMecanica who built it.
The other two at my place.
Made in thin wall 4130 ChroMo and only weighs 12kg complete with swing arm.
Notice the engine mounts on the rear, differing greatly from std Egli practice,  I asked for this as a bolted plate trapped between the swing arm is not in my opinion a recipe for rigidity.
Will send more as soon as I can find time to download the pics.

Nothing more to add really at this moment other than I have a spare cylinder head that I most definately will remove the skulls from and re-shape the combustion chambers extensively.

Regards,
Julian
 

Attachments

  • 12042695_1024104794321270_4374294218586162690_n.jpg
    12042695_1024104794321270_4374294218586162690_n.jpg
    73.8 KB · Views: 194
  • IMG_20160412_184647 small.jpg
    IMG_20160412_184647 small.jpg
    196.7 KB · Views: 409
  • IMG_20160408_104252 small.jpg
    IMG_20160408_104252 small.jpg
    193 KB · Views: 182
Very nice, like the rear engine mounts. It's about time we got some progress shots.

Now I've seen this on my I pad, only on phone before, as the 12mm nuts won't fit into the recess's, I presume the two long through bolts will be replaced with 4 x socket head cap screws, with the nuts on the inside of the lug mounts. Because the thought of two through bolts scares me. That's a lot of stress on those mounts.
 
Hi Chris,

Yes, HT bolts, don't worry, I hate the idea of studs also, these were only in for the setup and to hold the spacers in the post.

J
 
Somebody else is running a single chain on this engine, from memory a race bike.

Dont forget to put the "big pin" singles in.

Good luck

Andy
 
andychain said:
Somebody else is running a single chain on this engine, from memory a race bike.

Dont forget to put the "big pin" singles in.

Good luck

Andy

I know of an engine that has been running on a single row IWIS for ages.  1973 works engines had single row timing chains too, but with special sprockets and tensioners to suit.

piet
 
Back
Top