Britbike forum

Classic British SparesKlempf British PartsBaxter CycleThe Bonneville ShopLowbrow CustomsGirling Classic MotorcycleLucas Classic MotorcycleHepolite PistonsIndustrial tec supplyJob Cycle

Upgrade your membership to Premium Membership or Gold Membership or even Benefactor


New Sponsor post
10% Off Girling at The Bonneville Shop 2/3-2/9/23
by The Bonneville Shop - 02/03/23 6:14 pm
New FAQ post
News & Announcements
Premium members! 🌟
by Morgan aka admin - 02/04/23 2:40 pm
Buy BritBike staff a coffee ☕️ or pint 🍺
by Morgan aka admin - 01/15/23 9:29 am
Benefactor ✅
by Morgan aka admin - 01/08/23 8:38 pm
How to guides - Technical articles
ShoutChat
Comment Guidelines: Do post respectful and insightful comments. Don't flame, hate, spam.
Member Spotlight
Denis J
Denis J
Sacramento, CA
Posts: 485
Joined: November 2012
Top Posters(30 Days)
Lannis 84
DavidP 83
Top Likes Received (30 Days)
Kev. 34
DavidP 27
Newest Members
Uneasy Rider, Mally, Daveed, 70Triumph, Knight57Corv
12,392 Registered Users
Forum Statistics
Forums35
Topics76,551
Posts784,409
Members12,392
Most Online204
Jul 10th, 2022
Random Gallery photo
Photo posting tutorial

Previous Thread
Next Thread
Print Thread
Joined: Feb 2006
Posts: 966
Likes: 5
Ginge Offline OP
Britbike forum member
OP Offline
Britbike forum member
Joined: Feb 2006
Posts: 966
Likes: 5
Can anyone tell me how tight the lower engine mount bolt should be on a 1970 500? The one that runs laterally across the engine, just behind the sump plug.

My laptop has died and I can't read my workshop manual.

Am chasing a persistent oil leak in this area. The two steel collars that sit inboard of the lower frame rails seem loose. I can spin them with my fingers. If they are that loose then they aren't bearing on the crankcase and I think the bottom joint is weeping.

I know they leak here but mine is pretty bad.

Maybe they should spin to prevent chafing the alloy casing?

Thanks


'51 C11 in a '54 C10L frame. Back on the road...
'70 Triumph Trophy 500. Next on the bench for a refresh!
'72 Triumph Tiger 650. Back on the road...
Triumphs on eBay
Joined: Jun 2002
Posts: 10,478
Likes: 45
Britbike forum member
Offline
Britbike forum member
Joined: Jun 2002
Posts: 10,478
Likes: 45
Hi,

Originally Posted by Ginge
Can anyone tell me how tight the lower engine mount bolt should be on a 1970 500? The one that runs laterally across the engine, just behind the sump plug.

Nearest I can find in the 'C'-range manual is "Crankcase junction bolts ... 15 lb./ft." or "Crankcase junction studs ... 20 lb./ft." (sic).

However, on the T160 (which essentially isn't any different to any other Triumph in this area), "(Engine mounting bolts) Bottom" is "30/35 lb.ft."

Originally Posted by Ginge
The two steel collars that sit inboard of the lower frame rails seem loose. I can spin them with my fingers. If they are that loose then they aren't bearing on the crankcase
Maybe they should spin to prevent chafing the alloy casing?

confused

Maybe they aren't the correct length? When I built my '69, I measured the actual gap on the bike and made spacers to fit, rather than relying on the accuracy of some Far Eastern machinist without any responsibility for the quality or purpose of the parts. Also, if you make 'em/have 'em made to your measurements, no chance of you bending the lower frame rails when you tighten the stud/nut?

Hth.

Regards,

Joined: Aug 2011
Posts: 411
Britbike forum member
Offline
Britbike forum member
Joined: Aug 2011
Posts: 411
I'd just shim them up with washers and tighten the nuts to about 35ft/lbs.

davy

Joined: Sep 2014
Posts: 1,499
Likes: 37
Britbike forum member
Offline
Britbike forum member
Joined: Sep 2014
Posts: 1,499
Likes: 37
I'd guess that the principle is identical on a 500 to an OIF 750, in which case the nuts (on T140s it is a stud) or nut (if it's a bolt) have to be tightened sufficiently to clamp the spacers firmly between the frame and crankcase lugs. 35ft/lbs seems a good starting point. If 500s have 7/16" stud/bolt, you should be able to tighten a lot more than that safely.


If anything other than a blank space is visible here, something's wrong.
Joined: Dec 2010
Posts: 772
Likes: 6
Britbike forum member
Offline
Britbike forum member
Joined: Dec 2010
Posts: 772
Likes: 6
I know its a Triumph, but surely the engine should not be relying on the engine bolts to keep the oil inside it!

Joined: Feb 2006
Posts: 966
Likes: 5
Ginge Offline OP
Britbike forum member
OP Offline
Britbike forum member
Joined: Feb 2006
Posts: 966
Likes: 5
Thanks,

It's a single stud with a nut on each end. I gave it a tweak and tightened up one collar. I'll have to shim the other one. The gap is .035" so I don't think I'd get a washer in there.

Thanks for the thoughts.


'51 C11 in a '54 C10L frame. Back on the road...
'70 Triumph Trophy 500. Next on the bench for a refresh!
'72 Triumph Tiger 650. Back on the road...
Joined: Sep 2014
Posts: 1,499
Likes: 37
Britbike forum member
Offline
Britbike forum member
Joined: Sep 2014
Posts: 1,499
Likes: 37
If the bike has been used with the spacers free to move for some time, chances are they've worn some of the aluminium away from the crankcase lugs, therefore necessitating shims. Normally, if the spacers are free with the nuts slack, just tightening them fully will clamp them up.


If anything other than a blank space is visible here, something's wrong.
Joined: Nov 2008
Posts: 3,813
Likes: 80
Britbike forum member
Online Happy
Britbike forum member
Joined: Nov 2008
Posts: 3,813
Likes: 80
My laptop has died and I can't read my workshop manual.

Why I prefer the printed page.


1968 T120R
1972 T120RV
Any advice given is without a warranty expressed or implied.
Joined: Aug 2011
Posts: 411
Britbike forum member
Offline
Britbike forum member
Joined: Aug 2011
Posts: 411
Originally Posted by Ginge
Thanks,
It's a single stud with a nut on each end. I gave it a tweak and tightened up one collar. I'll have to shim the other one. The gap is .035" so I don't think I'd get a washer in there.

Thanks for the thoughts.


A stainless washer is 46 thou thick so if you loosen both nuts off you should get one in there without too much effort, 11 thou is nothing at that point between the rails.

davy

Joined: Jun 2002
Posts: 10,478
Likes: 45
Britbike forum member
Offline
Britbike forum member
Joined: Jun 2002
Posts: 10,478
Likes: 45
Hi Davy,

Originally Posted by Old Cafe Racer
A stainless washer is 46 thou thick

It might be in Oz but that's a weird size. Here in GB, 3/8" and 7/6" i.d. washers - whether stainless or other steel - are punched out of standard 1 mm. (~40 thou.) or 2 mm. (~80 thou.) plate or strip; given how they have to be produced for the producer to make a profit, I'd be surprised if they're different in much of the rest of the world.

Regards,

Joined: Sep 2014
Posts: 1,499
Likes: 37
Britbike forum member
Offline
Britbike forum member
Joined: Sep 2014
Posts: 1,499
Likes: 37
It seems you have a choice between springing the frame rails out 11 thou or so, or clamping them up 35 thou. I'd choose the latter, as long as the crankcase lugs haven't worn significantly (if they have, making up the difference with shims would seem a good way to go).


If anything other than a blank space is visible here, something's wrong.
Joined: Aug 2011
Posts: 411
Britbike forum member
Offline
Britbike forum member
Joined: Aug 2011
Posts: 411
Originally Posted by Stuart
Hi Davy,

Originally Posted by Old Cafe Racer
A stainless washer is 46 thou thick

It might be in Oz but that's a weird size. Here in GB, 3/8" and 7/6" i.d. washers - whether stainless or other steel - are punched out of standard 1 mm. (~40 thou.) or 2 mm. (~80 thou.) plate or strip; given how they have to be produced for the producer to make a profit, I'd be surprised if they're different in much of the rest of the world.

Regards,


Whatever Stuart, but I'm not about to argue with my vernier caliper on your account. I simply picked a stainless washer out of the box and measured it.
6 thou less would be in the OP's favour anyway.

davy


Moderated by  John Healy 

Link Copied to Clipboard
British Cycle SupplyMorries PlaceKlempf British PartsBSA Unit SinglesPodtronicVintage MagazineBritBike SponsorBritish Tools & FastenersBritBike Sponsor






© 1996-2023 britbike.com
Powered by UBB.threads™ PHP Forum Software 7.7.5