interesting bikes found randomly..

Anything you like about motorbikes
JackyJoll
Posts: 3741
Joined: Sun May 03, 2020 10:11 pm
Has thanked: 261 times
Been thanked: 1266 times

Re: interesting bikes found randomly..

Post by JackyJoll »

The Spin Doctor wrote: Fri Jul 23, 2021 11:22 am

What's with the tape round the downpipes?
Have you not seen that before?

Popular on the “hipster” style of modern cafe bike.

In theory, keeping heat in the exhaust has performance benefits.
The Spin Doctor
Posts: 4096
Joined: Mon Mar 16, 2020 6:17 pm
Has thanked: 2636 times
Been thanked: 1523 times

Re: interesting bikes found randomly..

Post by The Spin Doctor »

JackyJoll wrote: Fri Jul 23, 2021 12:32 pm Have you not seen that before?

Popular on the “hipster” style of modern cafe bike.

In theory, keeping heat in the exhaust has performance benefits.
I've seen it... I even remember it from the 70s! But I've never known why!

One explanation was that it helps performance by keeping heat in the exhaust, but I'm struggling to figure out any rationale for that.
"If a man does not keep pace with his companions, perhaps it is because he hears a different drummer." Henry David Thoreau
www.ko-fi.com/survivalskills www.survivalskillsridertraining.co.uk www.facebook.com/survivalskills
Mr. Dazzle
Posts: 13977
Joined: Mon Mar 16, 2020 7:57 pm
Location: Milton Keynes
Has thanked: 2552 times
Been thanked: 6262 times

Re: interesting bikes found randomly..

Post by Mr. Dazzle »

It changes the speed of sound in the gas and therefore changes the harmonics. Whether or not that is a benefit or just 'different' is often lost in the details. :D

Turbochargers can benefit from having higher inlet temps too, ultimately turbos extract work from the hot gas so hotter gas in means more available work.

You see it a lot in cars too, but thats mostly about underbonnet temperature.

Also helps prevent burning of your leg!
The Spin Doctor
Posts: 4096
Joined: Mon Mar 16, 2020 6:17 pm
Has thanked: 2636 times
Been thanked: 1523 times

Re: interesting bikes found randomly..

Post by The Spin Doctor »

Mr. Dazzle wrote: Fri Jul 23, 2021 3:15 pm It changes the speed of sound in the gas and therefore changes the harmonics. Whether or not that is a benefit or just 'different' is often lost in the details. :D

Turbochargers can benefit from having higher inlet temps too, ultimately turbos extract work from the hot gas so hotter gas in means more available work.

You see it a lot in cars too, but thats mostly about underbonnet temperature.

Also helps prevent burning of your leg!
Yebbut... I don't ride with my legs stuck out in front dangling alongside the downpipes ;)

Yorick will be along in a moment to tell me I'm weird like that. ;)
"If a man does not keep pace with his companions, perhaps it is because he hears a different drummer." Henry David Thoreau
www.ko-fi.com/survivalskills www.survivalskillsridertraining.co.uk www.facebook.com/survivalskills
cheb
Posts: 4910
Joined: Tue Mar 17, 2020 6:51 am
Been thanked: 2619 times

Re: interesting bikes found randomly..

Post by cheb »

I've read that it was Dr Joe Erlich and his work on 2ts that started it. The reasoning is that they got more power on the dyno that on the track and surmised that the pipes ran hotter on the dyno because of a lack of a cooling flow. Insulating the pipes on the track kept them at dyno temperature and got the missing power back.

I have no way of verifying if this it true so use your own judgement.
User avatar
Rockburner
Posts: 4380
Joined: Sun Mar 15, 2020 11:06 am
Location: Hiding in your blind spot
Has thanked: 7822 times
Been thanked: 2532 times

Re: interesting bikes found randomly..

Post by Rockburner »

cheb wrote: Fri Jul 23, 2021 4:42 pm so use your own judgement.
Is that genuinely a good idea?
non quod, sed quomodo
cheb
Posts: 4910
Joined: Tue Mar 17, 2020 6:51 am
Been thanked: 2619 times

Re: interesting bikes found randomly..

Post by cheb »

That depends on the user.
User avatar
Taipan
Posts: 13970
Joined: Sat Mar 14, 2020 1:48 pm
Location: Essex Riviera!
Has thanked: 15982 times
Been thanked: 10259 times

Re: interesting bikes found randomly..

Post by Taipan »

The Spin Doctor wrote: Fri Jul 23, 2021 11:24 am
v8-powered wrote: Fri Jul 23, 2021 11:06 am Quite like this - based on a Triumph Sprint 1997 vintage. https://www.returnofthecaferacers.com/t ... print-900/

I'll probably get lynched now but I rather like that too - improves on the original, I think.

I do like the right way up forks, as well.

The Triumph purists soon caught up with Spin...


Image
JackyJoll
Posts: 3741
Joined: Sun May 03, 2020 10:11 pm
Has thanked: 261 times
Been thanked: 1266 times

Re: interesting bikes found randomly..

Post by JackyJoll »

Taipan wrote: Fri Jul 23, 2021 7:06 pm
The Spin Doctor wrote: Fri Jul 23, 2021 11:24 am
v8-powered wrote: Fri Jul 23, 2021 11:06 am Quite like this - based on a Triumph Sprint 1997 vintage. https://www.returnofthecaferacers.com/t ... print-900/

I'll probably get lynched now but I rather like that too - improves on the original, I think.

I do like the right way up forks, as well.

The Triumph purists soon caught up with Spin...

There are Hinckley (and Thailand) Triumph purists now??
User avatar
derek badger
Posts: 898
Joined: Sat Mar 14, 2020 1:12 pm
Location: Surrey Hills
Has thanked: 769 times
Been thanked: 1135 times

Re: interesting bikes found randomly..

Post by derek badger »

500cc Jawa single with a supercharger and nitrous. It's not the prettiest, but I like it because it's been built using 'why the hell not?' school of thought and it looks fun.

Image

Image

Image

http://caferacersunited.com/supercharge ... KQPSByh1L0
JackyJoll
Posts: 3741
Joined: Sun May 03, 2020 10:11 pm
Has thanked: 261 times
Been thanked: 1266 times

Re: interesting bikes found randomly..

Post by JackyJoll »

Am I wrong to think about trying to ride it?

I don’t see it getting far with an unfiltered air intake pointing at the back tyre. Am I seeing that wrong?

I can’t see what keeps your leg out of the blower drive. Wouldn’t need a huge tin guard, just a bar across it.
User avatar
rodbargee
Posts: 1021
Joined: Sat Mar 14, 2020 1:30 pm
Location: N Yorks
Has thanked: 353 times
Been thanked: 980 times

Re: interesting bikes found randomly..

Post by rodbargee »

Image

Image

Ebay at the moment 22K
User avatar
weeksy
Site Admin
Posts: 23439
Joined: Sat Mar 14, 2020 12:08 pm
Has thanked: 5455 times
Been thanked: 13103 times

Re: interesting bikes found randomly..

Post by weeksy »

Don't like it. Not at all. Funny how different people value different things
JackyJoll
Posts: 3741
Joined: Sun May 03, 2020 10:11 pm
Has thanked: 261 times
Been thanked: 1266 times

Re: interesting bikes found randomly..

Post by JackyJoll »

It’s not even finished if you have to park on a block of wood!
User avatar
rodbargee
Posts: 1021
Joined: Sat Mar 14, 2020 1:30 pm
Location: N Yorks
Has thanked: 353 times
Been thanked: 980 times

Re: interesting bikes found randomly..

Post by rodbargee »

I wonder if the"occasion" of riding such a thing offsets the probable total pain in the arse it is to ride....

3 days to go place bets now My guess 42 K
User avatar
Taipan
Posts: 13970
Joined: Sat Mar 14, 2020 1:48 pm
Location: Essex Riviera!
Has thanked: 15982 times
Been thanked: 10259 times

Re: interesting bikes found randomly..

Post by Taipan »

weeksy wrote: Sat Jul 24, 2021 10:23 am Don't like it. Not at all. Funny how different people value different things
FWIW, me neither!
The Spin Doctor
Posts: 4096
Joined: Mon Mar 16, 2020 6:17 pm
Has thanked: 2636 times
Been thanked: 1523 times

Re: interesting bikes found randomly..

Post by The Spin Doctor »

derek badger wrote: Sat Jul 24, 2021 8:02 am 500cc Jawa single with a supercharger and nitrous. It's not the prettiest, but I like it because it's been built using 'why the hell not?' school of thought and it looks fun.
Madness... in a good sense!
"If a man does not keep pace with his companions, perhaps it is because he hears a different drummer." Henry David Thoreau
www.ko-fi.com/survivalskills www.survivalskillsridertraining.co.uk www.facebook.com/survivalskills
David
Posts: 2134
Joined: Tue Mar 17, 2020 8:50 am
Location: Top 'o the Worle
Has thanked: 218 times
Been thanked: 689 times

Re: interesting bikes found randomly..

Post by David »

rodbargee wrote: Sat Jul 24, 2021 10:16 am Image

Image

Ebay at the moment 22K
That is seriously nice!!!
User avatar
Skub
Posts: 12182
Joined: Mon Mar 16, 2020 5:32 pm
Location: Norn Iron
Has thanked: 9842 times
Been thanked: 10156 times

Re: interesting bikes found randomly..

Post by Skub »

An interesting stroker project close to me and for not a lot of money. I daresay parts will be like hen's teeth.

https://www.facebook.com/marketplace/it ... 864320"%7D

Image


Image
"Be kind to past versions of yourself that didn't know what you know now."
Walt Whitman
https://soundcloud.com/skub1955
User avatar
mangocrazy
Posts: 6934
Joined: Tue Dec 22, 2020 9:58 pm
Has thanked: 2408 times
Been thanked: 3638 times

Re: interesting bikes found randomly..

Post by mangocrazy »

rodbargee wrote: Sat Jul 24, 2021 10:16 am Image

Image

Ebay at the moment 22K
In the late 60s/early 70s that would have been the coolest of the cool. Now it's more a case of 'why did you vandalise a motorcycling icon, you moron?'
There is no cloud, just somebody else's computer.