BritBike Forum logo
BritBike Sponsor BritBike Sponsor BritBike Sponsor
BritBike Sponsor

BritBike Sponsor

BritBike Sponsor
BritBike Sponsor BritBike Sponsor BritBike Sponsor
The Bonneville Shop
Home | Sponsors, Newsletter | Regalia | Calendar | Bike Project | BritBike Museum | Spiders Cartoons, "OLD" BritBike Forum | DVD- Manuals & Parts books | BritBike Stickers & Decals
Upgrade to: Premium Membership | Premium Life Membership | Vendor Membership | Site Sponsor Membership
Member Spotlight
David Huybens
David Huybens
Australia
Posts: 57
Joined: December 2009
Show All Member Profiles 
Shout Box
Search eBay for motorcycle parts in following countries
Australia, Canada, France, Holland, Italy, United Kingdom, USA
Random Gallery photo
Who's Online Now
23 registered members (Andy Lorenz), 203 guests, and 373 spiders.
Key: Admin, Global Mod, Mod
Newest Members
John Rowley, Zoot, sal pisciotta, Shawn G, bemie
10528 Registered Users
Top Posters(30 Days)
franko 90
Lannis 85
NickL 66
Popular Topics(Views)
785,121 mail-order LSR
Forum Statistics
Forums34
Topics69,220
Posts674,261
Members10,528
Most Online3,995
Feb 13th, 2017
Like BritBike.com on Facebook

Previous Thread
Next Thread
Print Thread
Rate Thread
500 heads #754842
11/02/18 11:04 am
11/02/18 11:04 am
Joined: Jan 2006
Posts: 2,032
Asheville, NC
Mike Baker Offline OP
BritBike Forum member
Mike Baker  Offline OP
BritBike Forum member

Joined: Jan 2006
Posts: 2,032
Asheville, NC
There's a possibility of a 500 in the not too distant future. AHRMA has done some rule changes to where bearing motors and later frames are now allowed for classic 60's. All good IMO, as the new rules address reliability with the bushing and safety issues with the old style frame. They still spec a squish band head, though. My understanding is that one is stuck with a low compression motor with this head? Is there anything that could be done to later pistons to allow them to be used with the early head?
Thanks!

Support Your #1 BritBike Forum!

Check out British motorcycles for sale:
British Motorcycles on e-Bay UK, British motorcycles on e-Bay North America
Check out British motorcycles for sale:
British Motorcycles on e-Bay UK, British motorcycles on e-Bay North America
Re: 500 heads [Re: Mike Baker] #754843
11/02/18 11:13 am
11/02/18 11:13 am
Joined: Aug 2015
Posts: 1,309
Bolton Lancs UK
A
Andy Higham Offline
BritBike Forum member
Andy Higham  Offline
BritBike Forum member
A

Joined: Aug 2015
Posts: 1,309
Bolton Lancs UK
Maybe if you were more precise you may get some answers, at least make and model
A "500" could be about anything, Just about every manufacturer made a 500.


BSA B31 500cc "Stargazer"
Greeves 200cc "Blue Meanie"
Greeves 350
Greeves 360 Challenger
Suzuki GSX1100 EFE "Sorcerers Apprentice"
GM500cc sprint/LSR bike "Deofol"
Jawa 500cc "Llareggub"
2003 Aprilia RSV Mille "Lo Stregone"
'35 OK Supreme
'36 OK Supreme
Re: 500 heads [Re: Mike Baker] #754847
11/02/18 11:42 am
11/02/18 11:42 am
Joined: Jan 2006
Posts: 2,032
Asheville, NC
Mike Baker Offline OP
BritBike Forum member
Mike Baker  Offline OP
BritBike Forum member

Joined: Jan 2006
Posts: 2,032
Asheville, NC
Triumph

Re: 500 heads [Re: Mike Baker] #754854
11/02/18 3:15 pm
11/02/18 3:15 pm
Joined: Mar 2005
Posts: 10,270
Boston, Massachusetts
J
John Healy Offline
BritBike Forum member
John Healy  Offline
BritBike Forum member
J

Joined: Mar 2005
Posts: 10,270
Boston, Massachusetts
[Linked Image]

[Linked Image]

The pistons are blanks that need to be machined to match squish band. They are made by Aries. In different configurations we used these for years.

These can be cut to make up to 13:1 compression ratio.

Head - Oversize intake plus .060"; stock exhaust.

Ports to match rider ability and type of racing. AHRMA 6 - 8 lap racing doesn't work with close ration gearing so looking for more torque than raw hp.

Because of the valve angle of the squish band head, the faces of the valves need to be faced to
provide clearance at valve overlap.

Valve springs are a problem. R&D last only one, maybe two, race meetings as the bike needs to be run up to 9,000rpm
to make any use able torque/hp. Stock crankshafts have problems when you actually find some hp,

When you are lucky enough to find some real power crankshafts become a problem. Even Nourish cranks will break, but not as much as stock.

When you find some power the transmission main shaft kick starter bearing housing (bearing retaining circlip arrangement) needs to be modified to keep it from coming out of third.


Re: 500 heads [Re: Mike Baker] #754940
11/03/18 11:42 am
11/03/18 11:42 am
Joined: Jan 2006
Posts: 2,032
Asheville, NC
Mike Baker Offline OP
BritBike Forum member
Mike Baker  Offline OP
BritBike Forum member

Joined: Jan 2006
Posts: 2,032
Asheville, NC
Thanks, J. I'm certain an incredible amount of time and effort went into development of your 500's. What class(s) did you run the bike in? How competitive was it vs. the big Nortons et c? The edges on those valves look like they'd be pretty thin!
I'm not looking to go the 10/10's route. Rather something that can be raced for a season with basic maintenance. I suppose those Arias can be cut to a 10-11 compression ratio as easily as 13. Not cheap but do able. But nothing to be done with stock units? Or any other more or less off the shelf pistons?
Thanks for any ideas

Last edited by Mike Baker; 11/03/18 11:45 am.
Re: 500 heads [Re: Mike Baker] #755357
11/07/18 9:36 pm
11/07/18 9:36 pm
Joined: Mar 2009
Posts: 95
manchester england
W
wilksville Offline

BritBike Forum member
wilksville  Offline

BritBike Forum member
W

Joined: Mar 2009
Posts: 95
manchester england
Mr Healey,
Q1, is the head pictured above an E3991 casting ?
Q2, are rockerboxes interchangeable between years where the valve angle changed ?
Regard Peter


'74 T140V,'83 XR1000, C&J FLATTRACKER T140,
Re: 500 heads [Re: wilksville] #758413
12/07/18 4:42 am
12/07/18 4:42 am
Joined: Feb 2007
Posts: 2,282
Atlanta, GA USA
S
Semper Gumby Offline
BritBike Forum member
Semper Gumby  Offline
BritBike Forum member
S

Joined: Feb 2007
Posts: 2,282
Atlanta, GA USA
Hey Mike - Crikey I hope my 67 West coast Hornet is still good. I'd hate to build this bike and then not race in your class....


Secretly Mediocre....
Re: 500 heads [Re: Mike Baker] #758561
12/08/18 2:18 am
12/08/18 2:18 am
Joined: Jan 2006
Posts: 2,032
Asheville, NC
Mike Baker Offline OP
BritBike Forum member
Mike Baker  Offline OP
BritBike Forum member

Joined: Jan 2006
Posts: 2,032
Asheville, NC
So there I was starting to think you were all talk. Well I can assure you, Mr Bill, that the trusty 650 is going nowhere soon and you can count on some thrilling competition with me and other like minded hooligans.
Now..... where's Kevin R's so called track bike? Hmmmm?

Re: 500 heads [Re: Mike Baker] #758648
12/09/18 1:47 am
12/09/18 1:47 am
Joined: Dec 2013
Posts: 4,682
ohio, usa
kevin roberts Offline

DOPE
kevin roberts  Offline

DOPE

Joined: Dec 2013
Posts: 4,682
ohio, usa
i'm doin it, i'm doin it

i'm working 14-hour 400-mile days and my kids have been whining about broken trucks for two weeks, so i've been pulling steering wheels and repairing ignition locks.

the morgo is still on the lift waiting for me to shorten the chain for the 19-tooth gearbox sprocket.

two days off in two days.


The study of the art of motorcycle maintenance is really a miniature study of the art of rationality itself. Working on a motorcycle, working well, caring, is to become part of a process, to achieve an inner peace of mind. The motorcycle is primarily a mental phenomenon.

/robert_m_pirsig_
Re: 500 heads [Re: kevin roberts] #758961
12/11/18 9:22 pm
12/11/18 9:22 pm
Joined: May 2013
Posts: 5,224
West Yorkshire
Allan Gill Offline

BritBike Forum member
Allan Gill  Offline

BritBike Forum member

Joined: May 2013
Posts: 5,224
West Yorkshire
Originally Posted by kevin roberts
i'm doin it, i'm doin it

i'm working 14-hour 400-mile days and my kids have been whining about broken trucks for two weeks, so i've been pulling steering wheels and repairing ignition locks.

the morgo is still on the lift waiting for me to shorten the chain for the 19-tooth gearbox sprocket.

two days off in two days.



Sure as hell know that feeling Kevin, then soon as those 2 days arrive your so worn out, brain dead or have some other emergency you have to sort (maybe all 3) then you ha e to wait for all that time again.


beerchug
Re: 500 heads [Re: Mike Baker] #758988
12/12/18 2:30 am
12/12/18 2:30 am
Joined: Jan 2006
Posts: 2,032
Asheville, NC
Mike Baker Offline OP
BritBike Forum member
Mike Baker  Offline OP
BritBike Forum member

Joined: Jan 2006
Posts: 2,032
Asheville, NC
No pressure.
Roebling Road 21-24 Feb, 2019

Re: 500 heads [Re: Mike Baker] #759764
12/19/18 9:20 am
12/19/18 9:20 am
Joined: Feb 2007
Posts: 2,282
Atlanta, GA USA
S
Semper Gumby Offline
BritBike Forum member
Semper Gumby  Offline
BritBike Forum member
S

Joined: Feb 2007
Posts: 2,282
Atlanta, GA USA
Originally Posted by Mike Baker
No pressure.
Roebling Road 21-24 Feb, 2019


Picking up motor Friday.


Secretly Mediocre....

Moderated by  Allan Gill 


Home | Sponsors | Newsletter | Regalia | Calendar | Bike Project | BritBike Museum | Spiders Cartoons | "OLD" BritBike Forum | DVD- Manuals & Parts books | BritBike Stickers & Decals
Upgrade to: Premium Membership | Premium Life Membership | Vendor Membership | Site Sponsor Membership
Powered by UBB.threads™ PHP Forum Software 7.6.2