BritBike Forum logo
BritBike SponsorBritBike SponsorBritBike SponsorBritBike SponsorBritBike SponsorBritBike SponsorBritBike SponsorBritBike SponsorThe Bonneville ShopBritBike Sponsor SteadfastCyclesBritBike SponsorBritBike Sponsor
Upgrade to: Gold Membership | Premium Membership | Vendor Membership | Site Sponsor Membership
Electric Starter Roller
CLICK HERE to see VIDEO
How the Electric Roller Starter works.


ORDER on eBay. CLICK HERE!

Buy your Electric Roller Starter here
ShoutChat Box
Comment Guidelines: Do post respectful and insightful comments.
Buy BritBike staff a coffee
Buy BritBike's staff a coffeeStill here since 1996 serving BritBike enthusiasts..
Search eBay for motorcycle parts in following countries
Australia, Canada, France, Holland, Italy, United Kingdom, USA
Random Gallery photo
Member Spotlight
John Michl
John Michl
Keokuk, Ia
Posts: 250
Joined: December 2002
Show All Member Profiles 
Newest Members
B. Nicholson, AndrewQ, Jay999, davidlittle, Frank B
10938 Registered Users
Top Posters(30 Days)
franko 74
DavidP 60
Popular Topics(Views)
1,066,926 mail-order LSR
a word from..
Forum Statistics
Forums35
Topics68,249
Posts684,808
Members10,938
Most Online14,755
May 5th, 2019
Who's Online Now
69 registered members (Adam M.), 951 guests, and 869 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Page 3 of 3 1 2 3
Re: Head Gasket Impression in Head [Re: perfect.tommy] #759467 12/16/18 3:31 pm
Joined: Nov 2008
Posts: 2,994
D
desco Online Happy
BritBike Forum member
Online Happy
BritBike Forum member
D
Joined: Nov 2008
Posts: 2,994
+ 1 Hillbilly
There is a lot of misery out there due to people seeking perfection in an imperfect world.
On being a mechanic, I just keep removing bolts till something falls off.


1968 T120R
1972 T120RV
Any advice given is without a warranty expressed or implied.
Support Your #1 BritBike Forum!

Check out British motorcycles for sale:
British Motorcycles on e-Bay UK
British motorcycles on e-Bay North America
CLICK HERE to see VIDEO
How the Electric Roller Starter works.


ORDER on eBay. CLICK HERE!

Buy your Electric Roller Starter here
Re: Head Gasket Impression in Head [Re: Hillbilly bike] #759482 12/16/18 6:17 pm
Joined: Jun 2007
Posts: 6,596
HawaiianTiger Online Content
BritBike Forum member
Online Content
BritBike Forum member
Joined: Jun 2007
Posts: 6,596
Originally Posted by Hillbilly bike




..I learned to work on vehicles because I always drove junk that needed repairing at times.




+1


Bikes
1974 Commando
1985 Honda Nighthawk 650
1957 Thunderbird/T110 "Black Tiger"
Antique Fans: Loads of Emersons (Two six wingers) plus gyros and orbiters.
Re: Head Gasket Impression in Head [Re: desco] #759492 12/16/18 7:51 pm
Joined: Sep 2013
Posts: 65
perfect.tommy Offline OP
BritBike Forum member
OP Offline
BritBike Forum member
Joined: Sep 2013
Posts: 65
Desco,

I think you are missing the point. Being stranded on the wrong side of a mountain range because you had an engine failure... that's misery.

Having peace of mind knowing that your bike is not going to leave you stranded on a 3,000 mile trip is the end goal here.


1970 Triumph Tiger
Re: Head Gasket Impression in Head [Re: Hillbilly bike] #759494 12/16/18 8:15 pm
Joined: Sep 2013
Posts: 65
perfect.tommy Offline OP
BritBike Forum member
OP Offline
BritBike Forum member
Joined: Sep 2013
Posts: 65
Hillbilly,

The bike has been apart for a number of reasons, some of which I will list here. I sense you may think that I am just taking the bike apart looking for problems, but I can assure you I would rather be riding than wrenching.

The head came off the first time for a full engine rebuild.

2) The cases were split due to low oil pressure. The machine shop had ground the journals on a taper.

3) The cases were split again. The second machine shop ground the journals with excessive clearance. At this point I finally invested in some quality micrometers. I eventually found a good machinist locally, though this is really a dying trade... and dying quite literally. My crank balancer passed away a few years ago and he had been doing it his whole life. Many of the manual machinists who are left are quite old. There has been very little interest from younger generations to pick up this trade, especially with the advent of CNC and so much outsourcing of work to China, etc.

4) Head came off another time to instal a big bore kit. At this time I invested in a second head which was rebuilt by Rob Hall at Hall's Custom Vintage in North Carolina. Nice work.

5) As mentioned earlier, there were a number of times where the gasket did not seal and leaked between cylinders.

6) The head is off now not because it leaked, but because I am unhappy with the cam change I made on the last teardown. I'm re-installing my previous set of cams because they come on cam lower in the rpm range.

I hope this satisfies your curiosity.


1970 Triumph Tiger
Re: Head Gasket Impression in Head [Re: NickL] #759516 12/16/18 11:23 pm
Joined: Sep 2013
Posts: 65
perfect.tommy Offline OP
BritBike Forum member
OP Offline
BritBike Forum member
Joined: Sep 2013
Posts: 65
Well hopefully now that you have regained your sense of superiority, we can get back to focussing on the topic at hand.

Perhaps you fell out of your mother's womb with a wrench in your hand, but some of us had to learn our workshop skills from the ground up. And a lot of those learnt skills came from making mistakes. Very few people own precision measuring tools when they are first learning the trade. That's what you rely on your machinist for. Unfortunately I chose inept machinists to do the work. That's part of the learning curve.

If you want to hangout on the britbike forum and shame people for not knowing as much as you, or for the mistakes they may have made in the past, I think you are here for the wrong reasons. We are here to learn and help each other.

If you are going to use quotation marks, I said "lower standards". I made no comments on your engineering skills.


1970 Triumph Tiger
Re: Head Gasket Impression in Head [Re: perfect.tommy] #759536 12/17/18 3:05 am
Joined: Feb 2008
Posts: 4,585
Tridentman Online Content
BritBike Forum member
Online Content
BritBike Forum member
Joined: Feb 2008
Posts: 4,585
You are too modest, Nick---as everyone else on this board will tell you.
However---a word to both you and Tommy---perfect or imperfect-----
I spent my career in manufacturing engineered products.
There we had a saying:
"The guy who never made a mistake never made anything".
So lets concentrate on these intriguing and compelling old Brit bikes rather than gunning for each other.
HTH

Re: Head Gasket Impression in Head [Re: Tridentman] #759550 12/17/18 6:58 am
Joined: Sep 2013
Posts: 65
perfect.tommy Offline OP
BritBike Forum member
OP Offline
BritBike Forum member
Joined: Sep 2013
Posts: 65
I hear that.

And apologies again Nick if I came off a little hot.

Let's keep making mistakes. And learning.


1970 Triumph Tiger
Re: Head Gasket Impression in Head [Re: perfect.tommy] #759568 12/17/18 1:16 pm
Joined: Apr 2014
Posts: 233
Hermit Offline
BritBike Forum member
Offline
BritBike Forum member
Joined: Apr 2014
Posts: 233
NickL, perfect.tommy - Well done lads!

We all come here to learn. Not everything we learn is about motorbikes. Sometimes we learn about ourselves and others. All good.


Bruce Miller
aka The Hermit
The Bonnie Ref: https://www.hermit.cc/tmc/om/manual.htm
Re: Head Gasket Impression in Head [Re: Hermit] #759600 12/17/18 4:03 pm
Joined: Dec 2006
Posts: 4,104
B
btour Offline
BritBike Forum member
Offline
BritBike Forum member
B
Joined: Dec 2006
Posts: 4,104
Originally Posted by Hermit
NickL, perfect.tommy - Well done lads!

We all come here to learn. Not everything we learn is about motorbikes. Sometimes we learn about ourselves and others. All good.


Well said.


Bob, Lifetime bike: '71 T120R, bought in '71 at Ken Heanes, England.
Re: Head Gasket Impression in Head [Re: perfect.tommy] #759680 12/18/18 5:47 am
Joined: Jan 2017
Posts: 875
T
TR7RVMan Online Content
BritBike Forum member
Online Content
BritBike Forum member
T
Joined: Jan 2017
Posts: 875
Hi Tommy, Was looking at MAP website head gaskets.

Dead soft or normal... What's the difference in softness? Meaning how much softer? Would be curious to know. If you heated a normal gasket bright red to anneal would it then be dead soft or not?

Or.... are they a different copper alloy?

Is it feasible the dead soft are too soft & allowing head to flex compressing gasket .0015"?


What does the gasket measure in many places? Is the head flexing down at the outside end bolts?


How much flex does it take to make a sealing difference in the valve seats?


New question. How thick is your head measured from top to head gasket surface using depth gage?


On the '69 Bonnie I did recently I measured. Uncut head original with known history. The '69 head is very similar to your '70.

OUTER: RF 2.781", RR 2.86", LF 2.780", LR 2.787"

INNER: RF 2.799", RR 2.793", LF 2.799", LR 2.790"

CENTER 2.318".

If you draw this out, clearly the head was machined at a slope with rear of head thinner. Yet the rocker box surface is flat so it must have been machined this way from new. Yet the outer bolts are opposite with the thicker in rear. In actual practice this head is working good with no leaks or seeps at box gaskets or head gaskets.

In prior discussions I have in my notes the nominal head thickness was 2.755" to box gasket surface. Another discussion put head thickness new at 2.785-2.795". Triumph gives no spec I could find. My TR7RV head was skimmed aprox. .009". I didn't measure it before, dumb I know, but was back in 70s. After it measures 2.775-2.785". Sloping about 45deg angle across head with thicker on front. Was this from the skim or factory?? I don't know. Again rocker box surface is flat. No leaks from this head either. Again old copper gaskets crushed only about .001" and are fairly flat in crush.


Lastly you said your crank balancer passed. Sorry to hear that. Indeed this is common these days. Did you balance the crank on this motor? What factor did you use? On the '69 with light flywheel used 68%. A huge improvement 60-70 mph. Prior it was awful at freeway speeds. I have much interest in balancing as well.

Interesting stuff.
Don






1973 Tiger 750
Re: Head Gasket Impression in Head [Re: TR7RVMan] #759685 12/18/18 7:46 am
Joined: Aug 2014
Posts: 1,815
Triless Offline
BritBike Forum member
Offline
BritBike Forum member
Joined: Aug 2014
Posts: 1,815
How complex and critical things have become ! Admittedly, I was a late starter, only getting into motorcycles in 1970, aged 17, but the information then, passed on by the old timers, held true ! I got my first Triumph in 1976 ( bought new, and still in my possession !), and the then available knowledge , still held true !
I can remember quite a few Triumphs being rebuilt with the then available genuine parts, and which went on for reasonable mileages ! And , believe me, many of these rebuilds weren't "tool room " jobs !
Now, it seems that parts available today ( of which I have some that surpass anything available in the day ) must be the reason why Triumphs, for instance, must be rebuilt to standards of far higher than that of the original factory builds! To compensate for builder ineptitude ?
I'm not meaning to be disparaging of the gifted few who can build to the standards of factory racers, but the production bikes never were, and ( mostly) functioned satisfactorily .
Cleanliness and factory torque and adherance to clearances are the keys to successful rebuilds !
That's my take, so, in the words of Harry " the Breaker " Morant, to his firing squad, " Blast away, you bastards !"

Page 3 of 3 1 2 3

Moderated by  John Healy 

Home | Sponsors | Newsletter | Regalia | Calendar | Bike Project | BritBike Museum | Spiders Cartoons | DVD- Manuals & Parts books
Upgrade to: Gold Membership | Premium Membership | Vendor Membership | Site Sponsor Membership
CLICK HERE to see VIDEO
How the Electric Roller Starter works.


ORDER on eBay. CLICK HERE!

Buy your Electric Roller Starter here
Powered by UBB.threads™ PHP Forum Software 7.7.3