By continuing to use this site, you agree to our use of cookies. Find out more
Forum sponsored by:
Forum sponsored by Allendale Jan 24th

Motorcycle General Discussion

All Topics | Latest Posts

Search for:  in Thread Title in  
Lathejack01/11/2015 23:12:22
309 forum posts
329 photos

Only the short lived 8 valve head TSS Bonneville had the rocker shafts supported in the head casting, but still with seperate covers. This at least stopped the pushrods from trying to lift off the rocker covers. The standard four valve engines retained separate individual rocker boxes containing the rocker shafts.

BSA unit twins were better with rocker shafts in the head, and a nice large one piece finned cover. You know, I am beginning to like BSA's more and more. I have never ridden a BSA twin, in fact I had never ridden any BSA until I bought mine a few months ago.

BSA stopped building bikes in 1973, so by the 1980's, when I was riding bikes, most BSA's I came across were broken non runners festering away at the back of people's garages and sheds. The bikes I bought had to be working bikes, as I rode them as everyday transport all year round. Good working Triumphs were plentiful and I had quite a few of those, plus one T150 Trident, and some great Japanese bikes of the 70's and 80's. So BSA's have always been a bit of a mystery to me, until now.

Edited By Lathejack on 01/11/2015 23:14:24

Edited By Lathejack on 01/11/2015 23:30:32

Edited By Lathejack on 01/11/2015 23:31:59

Edited By Lathejack on 01/11/2015 23:38:35

Breva01/11/2015 23:18:38
avatar
83 forum posts
7 photos

wood_bike2.jpg

Maybe a little short on ground clearance?

Hopper01/11/2015 23:27:42
avatar
5505 forum posts
137 photos
Posted by Breva on 01/11/2015 23:18:38:

wood_bike2.jpg

Maybe a little short on ground clearance?

Wooden bike wooden corner?

Hopper01/11/2015 23:31:59
avatar
5505 forum posts
137 photos

I never could keep any of my triples' top ends oil tight for very long. Yet the 750 Bonnie I had was never a problem. And my Harley Sportster has the same sort of detachable rocker boxes that hold the rocker spindles and it has never leaked. The Harley will squeeze the gasket out if any kind of sealant is applied to the gaskets but fitted dry they work 100 per cent. But I tried everything on those triples and never could get them to stay clean and dry for more than a few thousand miles.

thaiguzzi02/11/2015 03:04:08
avatar
703 forum posts
131 photos

British bikes = oil leaks. Complete fallacy. Only std factory bikes. When rebuilding, it is not only renovate, repair, replace, but blueprint, blueprint, blueprint. You will then have an oil leak free British motorcycle. The same can be said for 60's-70's British, American and Italian electrics. Purchase the motorcycle, rip the std wiring harness out, bin it, and blueprint the electrics and add a custom harness.

Back in the day, Norfolk Police had Moto Guzzi 850 T3 police bikes, at 50k miles, they were auctioned off. Many of my friends purchased these, ripped the harness out, re-wired, and had a completely reliable motorcycle that would go anywhere inc long trips abroad with zero problems for another 50k with minimal basic maintenance. Thats 100k miles without lifting the heads.

thaiguzzi02/11/2015 03:07:23
avatar
703 forum posts
131 photos

Agree, Triumph rocker box design can be made long term oil leak free. Gaskets, design and materials have moved on in the last 20 years for Brit bikes, compared to the std crap that was available prior by the original manufacturers.

will hawkes02/11/2015 08:39:32
20 forum posts

with careful assembly any british engine will be totally free of leaks and reliable,none of my old panthers leak and my normal transport a 1937 panther mod 85 has now done 20.000 miles in the last couple of years cruises at 70 has 12 volt electrics (old dynamo i converted ) and has been totally reliable the old mz leaks more from the gearbox than the old ones , i have one that leaks a 95mph 250 panther racer but as there are no covers to keep the oil in i know when it stops leaking its time to bung some more castrol r in, will

MadMike02/11/2015 10:14:43
223 forum posts
4 photos

As a long time motorcyclist with a few bikes I have been reading this general discussion with more than a little interest. I have very strong views about leaking British bikes. I have a few in my garage, and have until a year ago had a lot more. My garage has fitted carpet and as you can imagine oil leaks would be a major problem. They have all been rebuilt, except for my 2012 Triumph Thruxton and my recently purchased Triumph 5TA Speed Twin. The former does not leak and the latter is currently on my work bench awaiting some serious spannering. In order to prevent my bikes leaking I have a very simple technique...............if they have the audacity to drip oil, I shout at them very loudly. They don't do it again.

Whilst I read this site every day, and occasionally post on here the truth is that I do not make models. My machines are used to make parts for my bikes and for friends bikes, mostly in stainless steel.

It's good to see so many motorcyclists on here. Long may it continue.

Hopper02/11/2015 11:24:52
avatar
5505 forum posts
137 photos

A nice model Harley Knucklehead. Not mine, but found on the net some time back. Built by Jerry Kieffer in the USofA, over about eight years. More pics of the finished model here

**LINK**

Even the speedo works!!

Mike Poole10/11/2015 23:12:58
avatar
Moderator
3047 forum posts
72 photos
Posted by thaiguzzi on 02/11/2015 03:04:08:

British bikes = oil leaks. Complete fallacy. Only std factory bikes. When rebuilding, it is not only renovate, repair, replace, but blueprint, blueprint, blueprint. You will then have an oil leak free British motorcycle. The same can be said for 60's-70's British, American and Italian electrics. Purchase the motorcycle, rip the std wiring harness out, bin it, and blueprint the electrics and add a custom harness.

I think Les Williams knew a bit about building Tridents but probably the most famous production racing Trident Slippery Sam, built by Les got its name from a bad oil leak. Blueprinting a flawed design will not solve a fundamental problem.

Mike

John Stevenson10/11/2015 23:58:30
avatar
Moderator
5068 forum posts
3 photos

Even the works wooden ones leak oil, shouldn't that be sawdust ?

Grotto11/11/2015 08:24:50
144 forum posts
88 photos

My 1969 Triumph Trophy is sort of oil tight since its rebuild. Only problem is the alloy head seems to be sponge-like. Doesn't leak oil from any of the joints, but it's become porous from age, and weeps small amounts of oil where there are no joints. Not uncommon apparently.

Hopper11/11/2015 08:29:53
avatar
5505 forum posts
137 photos
Posted by Grotto on 11/11/2015 08:24:50:

My 1969 Triumph Trophy is sort of oil tight since its rebuild. Only problem is the alloy head seems to be sponge-like. Doesn't leak oil from any of the joints, but it's become porous from age, and weeps small amounts of oil where there are no joints. Not uncommon apparently.

I had a 69 BSA Thunderbolt in about 1973 that had the same problem. Found out years later that there was a big batch of porous head castings that year. Probably the same supplier for both factories.

Beadblasting the inside of the rocker cavities and rocker boxes and painting them with Glyptal (sp?) casting sealer paint is a common solution today. But we didn't know anything about either of them back then.

MichaelR11/11/2015 09:14:11
avatar
440 forum posts
83 photos

Custom Pan Head Chopper "Wood" Here

Mike.

Mike Poole11/11/2015 11:16:06
avatar
Moderator
3047 forum posts
72 photos

Sound like a good ride Hopper, 6000 miles in the UK is not a trip you can easily make, the four points of Britain is only about 2500 miles. Other trips are on though once you get over the channel like how many countries you can visit in 24 hours. I see Harley's as bikes for wide open spaces like the US and Oz, in the UK i feel there are better tools for our type of roads. However there is a significant number of Harley's in the UK and a lot do fit the weekend warrior model that I mentioned. This always provokes a lively debate like the Brit vs Jap argument that still rumbles on even though I was a youth when it started and am now nearly 60.

Mike

Circlip11/11/2015 11:52:13
1327 forum posts

" This always provokes a lively debate like the Brit vs Jap argument that still rumbles on even though I was a youth when it started and am now nearly 60."

Yep, and I'm nearly 70 and proper bikes don't have electric start and indicators despite Mr Honda's "Dream".

On the Hardly theme, there's a British HQ for one of the international bike groups about 700yds from me. Despite the derision on the Yankee twins reliability, a few years ago they had some sort of "Meet". Like a flock of vultures, on the Saturday afternoon, they decided to depart and although they might have broken down at the end of the road, the peace was disturbed for at least five minutes solid (NO exaggeration) with thunderous Vee-twins two and three abreast hurtling past the house, and no, they weren't going round the block and back again. Pity I didn't have a camera available at the time. Sound wise, remember the Luftwaffe dispatch in front of Goering in "Battle of Britain".

Regards Ian

Involute Curve11/11/2015 13:52:53
avatar
337 forum posts
107 photos

A breather valve from a modern bike pretty much cures a lot of porous casting leaks, and helps enormously with all oils leaks on old classic bikes, most parallel twins tend to pump up the crank cases effectively forcing the oil out, these valves create a vacuum which helps a lot, and its easy to do.

What still puzzles me, is how come Triumph BSA etc. became the last survivor of the British bike industry, if you visit the bike museum at Birmingham, other manufacturers stuff was way ahead of both, in quality and design, I can only guess it was political or bad management or both.

Shaun

Gordon W11/11/2015 14:02:47
2011 forum posts

Re oil leaks- 2CV's horizontal twins, seldom leak oil, due to the layout and a very good, simple ,breather valve. Old Triumph twins- our cure was to wear a welly on the right foot.

Ian Abbott11/11/2015 15:42:44
avatar
279 forum posts
21 photos

Not too long ago I got stuck behind a bunch of brand new V twins without silencers, spread out all over the road for about ten miles coming out of Plymouth. The racket was so bad, I had to rely on the tach. to know when to change gear though the 500 single wasn't that quiet either. In the end I had to pull over with concussion and a splitting headache from the battering to let them get clear. They all looked like off duty, mid life crisis accountants, dressed for the golf course in shorts and T shirts, waiting for a dose of road rash.

I think my "real motorcyclist' prejudice is showing……. Or maybe it's just jealousy 'cos I can't ride anymore.

Ian

duncan webster11/11/2015 15:50:19
3443 forum posts
63 photos

When I worked in gas turbines (a very long time ago!) we used to have aluminium castings vacuum impregnated with resin to prevent any porosity issues. Whether there are still firms who do this, and whether it can be done when the casting is already soaked in oil I do not know

All Topics | Latest Posts

Please login to post a reply.

Magazine Locator

Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!

Find Model Engineer & Model Engineers' Workshop

Latest Forum Posts
Support Our Partners
Warco
rapid Direct
Dreweatts
cowells
walker midge
emcomachinetools
Eccentric July 5 2018
JD Metals
Eccentric Engineering
Subscription Offer

Latest "For Sale" Ads
Latest "Wanted" Ads
Get In Touch!

Do you want to contact the Model Engineer and Model Engineers' Workshop team?

You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.

Click THIS LINK for full contact details.

For subscription issues please see THIS LINK.

Digital Back Issues

Social Media online

'Like' us on Facebook
Follow us on Facebook

Follow us on Twitter
 Twitter Logo

Pin us on Pinterest