BritBike Forum logo
BritBike Sponsor BritBike Sponsor BritBike Sponsor
BritBike Sponsor

BritBike Sponsor

BritBike Sponsor
BritBike Sponsor BritBike Sponsor BritBike Sponsor
The Bonneville Shop JRC Engineering dealers
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
CaptainPugwash
CaptainPugwash
Conisbrough,Yorkshire, UK
Posts: 69
Joined: November 2008
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
17 registered members (Bluehighways), 175 guests, and 384 spiders.
Key: Admin, Global Mod, Mod
Newest Members
Davenz13, Sean65, Rerock, pkuzyk, Hunter S
10476 Registered Users
Top Posters(30 Days)
NickL 85
franko 72
Triless 67
Popular Topics(Views)
747,234 mail-order LSR
Forum Statistics
Forums34
Topics68,821
Posts670,336
Members10,476
Most Online3,995
Feb 13th, 2017
Like BritBike.com on Facebook

Previous Thread
Next Thread
Print Thread
Rate Thread
A65 big ends #588028
03/01/15 5:52 pm
03/01/15 5:52 pm
Joined: Jan 2006
Posts: 1,999
Maryland
JD Offline OP

Moto-Amish
JD  Offline OP

Moto-Amish

Joined: Jan 2006
Posts: 1,999
Maryland
Hey gents, I'm putting my '70 A65L back together after having some machine shop work completed by Bill Coleman in Baltimore after numerous recommendations to use him. I had about 2500 miles on the bike since my last rebuild, but wanted to take care of some nagging problems. 2500 miles ago, I had the journals ground to .010 under and the bike ran fine after that. I just put the connecting rods back on with new bearings, but they feel a little bit tight. We're not talking outright binding, but I have to give the connecting rod a little nudge for it to fall on its own. I also tried using the old bearings, but had the same issue. No new work was done on the crankshaft.

Mr. Coleman checked the crankshaft journal tolerances and said they were good. I checked the tolerances between the connecting rod big ends with bearings and the journals. My calipers said .0015" tolerance. I also use plastigauge which indicated it was between .001" and .0015" tolerance, but more toward the .001" side. The manual says .001"-.0025" bearing diametrical clearance, so I assume I'm within the tolerances? As it ran fine before, should I not worry about it and reassemble, or is this an issue?


Josh
Support your #1 BSA Forum and our favorite sponsors

Check out BSA on e-bay: BSA Parts in UK, BSA Motorcycles in UK, BSA Parts in North America, BSA Motorcycles in North America

 
Re: A65 big ends [Re: JD] #588045
03/01/15 7:17 pm
03/01/15 7:17 pm
Joined: Aug 2001
Posts: 4,242
argyll. scotland, uk
gavin eisler Online content
BritBike Forum member
gavin eisler  Online Content
BritBike Forum member

Joined: Aug 2001
Posts: 4,242
argyll. scotland, uk
It looks/reads as fine to me, for your own curiosity , try heating the rods with a hot air gun and see if they fall more freely.
I like plastiguage and your readings seem good to go.


71 Devimead A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
Re: A65 big ends [Re: JD] #588049
03/01/15 7:43 pm
03/01/15 7:43 pm
Joined: May 2013
Posts: 5,125
Rotherham - S. Yorkshire
Allan Gill Offline

BritBike Forum member
Allan Gill  Offline

BritBike Forum member

Joined: May 2013
Posts: 5,125
Rotherham - S. Yorkshire
This may sound like a daft solution but try bring the lump ( crank, rods) into the warmth of the house.

On my current build, the rods showed zero play on the rods, however when I put the micrometer ( calibrated) on the journals they both read .005" under spec. As it was about 1°c when I measured the journals I decided to bring the crank and the micrometer into the house for a couple of days. After the first day the journals still felt very cold, after the second the whole crank felt warmer so I measured again ( about 16°c) the journal size had grown upto the specs written in the book.

Don't forget to use assembly lube on the shells when installing.


beerchug
Re: A65 big ends [Re: JD] #588187
03/02/15 4:18 pm
03/02/15 4:18 pm
Joined: Jan 2006
Posts: 1,999
Maryland
JD Offline OP

Moto-Amish
JD  Offline OP

Moto-Amish

Joined: Jan 2006
Posts: 1,999
Maryland
Yeah, crankshaft and con rods are inside...have been for almost a week since it's too cold to work outside. I might try heating up the rods to see how easily they fall. Either way, it looks like I'm going to keep them as-is.


Josh
Re: A65 big ends [Re: JD] #588433
03/04/15 9:42 am
03/04/15 9:42 am
Joined: Nov 2011
Posts: 80
NH
GreenMonster Offline
BritBike Forum member
GreenMonster  Offline
BritBike Forum member

Joined: Nov 2011
Posts: 80
NH
Hello JD:

If the rod journals are both @ tdc it will take a bit of a nudge to get that lump to move.

Obviously their are other things that will cause the rotating assy. to drag.

Did your machinist line ream and hone your main bushing and cam bushings?

Hope he left the correct chamfere on the rod journals.

During the assy. of the engine did you check the torque required to turn the crank after each step.

Remember that things like timing gear and primary alignment also the oil pump can be an issue.

Was the crankshaft end float checked after the primary assy. was installed? .001 from what I remember is to tight.







Never Allow The Radical Views Of The Few To Infringe On The Constitutional Rights Of The Many
Re: A65 big ends [Re: JD] #588456
03/04/15 12:51 pm
03/04/15 12:51 pm
Joined: Aug 2001
Posts: 4,242
argyll. scotland, uk
gavin eisler Online content
BritBike Forum member
gavin eisler  Online Content
BritBike Forum member

Joined: Aug 2001
Posts: 4,242
argyll. scotland, uk
I read it as just the conrods seemed tight.


71 Devimead A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
Re: A65 big ends [Re: gavin eisler] #588502
03/04/15 5:31 pm
03/04/15 5:31 pm
Joined: May 2013
Posts: 5,125
Rotherham - S. Yorkshire
Allan Gill Offline

BritBike Forum member
Allan Gill  Offline

BritBike Forum member

Joined: May 2013
Posts: 5,125
Rotherham - S. Yorkshire
Originally Posted by gavin eisler
I read it as just the conrods seemed tight.


+1 now we have fabricated a cam issue grin


beerchug
Re: A65 big ends [Re: JD] #588549
03/04/15 11:01 pm
03/04/15 11:01 pm
Joined: Jan 2006
Posts: 1,999
Maryland
JD Offline OP

Moto-Amish
JD  Offline OP

Moto-Amish

Joined: Jan 2006
Posts: 1,999
Maryland
I appreciate the advice GM, but Gavin, you're right. The query was just for the con rods.


Josh
Re: A65 big ends [Re: JD] #588557
03/05/15 12:02 am
03/05/15 12:02 am
Joined: Oct 2001
Posts: 541
Howard City, MI
E
Ed V Offline

Sponsor Member
Ed V  Offline

Sponsor Member
E

Joined: Oct 2001
Posts: 541
Howard City, MI
Have you checked your con rod big ends to be sure they are round? I find many of them are not and this will cause the tight feeling you are noticing even though your measurements say you are ok.

Re: A65 big ends [Re: JD] #588628
03/05/15 12:13 pm
03/05/15 12:13 pm
Joined: Jan 2006
Posts: 1,999
Maryland
JD Offline OP

Moto-Amish
JD  Offline OP

Moto-Amish

Joined: Jan 2006
Posts: 1,999
Maryland
Hiya Ed, yes, the machinist checked them out as well as rechecking the crankshaft journals. I also checked both of them and found no issues.


Josh

Moderated by  Allan Gill, Jon W. Whitley 


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