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Messages - twolitre

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1
British Bikes / Re: Identification please!
« on: January 24, 2014, 11:48:03 AM »
Sorry, I have not been able to extract it from the Small Motorhome Forum.
Up to now I thought that Forum had a big advantage over this and most others in that pictures can be copied into it straight from a file on the PC without having to mess about with Photobucket orsimilar.
It seems copying them back is another story.
I'm afraid I have given up!
Jim.

2
British Bikes / Re: Identification please!
« on: January 20, 2014, 09:25:33 PM »
Sorry everyone.
I right clicked on the image on another forum and selected "copy URL" which I transferred to this forum.
It DID work for me, but now I realise that that was probably because I am permanently logged on to that forum.
I'm not much of a computerbuff, but I am trying to sort it out.
Jim.

3
British Bikes / Identification please!
« on: January 20, 2014, 03:05:53 PM »
I have been asked whether I could identify this bike. At least the crew are British so the bike may be.
The Cylinder looks almost as if it may be water cooled, but no radiator is visible. I have no idea though.
The driver is the father of the person wishing to know.
Can anyone help?

http://www.smallmotorhome.co.uk/forum/attachment.php?attachmentid=5845&d=1320591981

I imagine when that gun was fired it probably went backwards!
Jim.

4
British Bikes / Re: Head Gasket blow.
« on: October 19, 2013, 08:52:17 AM »
Oh my God!
I have tried to explain you the solid copper gasket HAS a dark mark on it indicating gas leakage!
Hence suspecting lack of pressure on the gasket caused by too much liner sticking out above the gaslet face on the barrels. I was only trying to find out whether the company which re-lined the barrels and bored them had wrongly positioned the liner.
I never mentioned nor believed that piston or ring leakage is a problem on this engine.
THe mass of the liner sticking up is too large for a hot spot, especially as it is adjacent and touching the solid copper gasket. Copper having an extremely high heat conductivity. 
Thank you for the information you have supplied. I will take it from there. I would rather accept the Triumph service sheet recommendation than your speculation.
Jim.

5
British Bikes / Re: Head Gasket blow.
« on: October 18, 2013, 11:03:48 PM »
I used the term "blow by" because the gasket was not blown, but evidence a gas escaping past it was shown by a darker part of the solid gasket surface. That led to a suspicion that the "nip" on the gasket was insufficient. Piston blow by is NOT a problem after 1000 miles.
Since the gasket is outside the protruding SHRINK FIT liner all that really matters is that the liner protrusion is not sufficient to prevent gasket compression. Which is the reason for trying to determine the recommended dimension.
I don't think that a small gap will have much effect except to perhaps lower the compression ratio by an infinitesimal amount. I think it is important that there IS a small gap (measuring "thous") to ensure gasket sealing. I don't see that a "hot spot" is at all likely.
Jim.

6
British Bikes / Re: Head Gasket blow.
« on: October 18, 2013, 09:39:25 PM »
Thank you Wetdog. You have answered my question.
The lip on my pre-1956 (1954actually) is 0.165 in. as posted earlier. i.e. 40 thou more than the service sheet quotes. Though not the 0.3125 in. original height quoted.
It seems in line with my suspicion. I will reduce it to 0.250 in tomorrow and continue the re-build.
I did feel that the lip was too high to allow all the tightening torque to be transmitted to the gasket.
Jim.

7
British Bikes / Re: Head Gasket blow.
« on: October 18, 2013, 04:36:53 PM »
how does the oil return from the head ? is yours fitted with the external returns to the lower section of the push rod tube ?

Yes.

8
British Bikes / Re: Head Gasket blow.
« on: October 18, 2013, 03:46:32 PM »
The standard 5T has iron barrels. The (shrunk in) liner stands proud like a spigot and the gasket is designed to locate on the "spigot", keeping all bolt holes aligned perfectly.
Rex, I am trying to find out how far the liner should stand up above the cast barrels top surface where the head gasket sits.
Fairly obviously I did not have the equipment to fit new liners etc. and left it to an engineering firm (now disappeared!). I trusted them to fit the liners properly and never took any measurements myself.
I feel I need to hone one bore slightly,before re-building,  because one piston is really an unhealthily tight fit at the top of its bore, where it needs a push (even with no rings) to help it all the way through.
Of course, with ring gapping being checked lower in the bore and pistons fitted at the cylinder barrel bottom, that problem escaped notice. Amazingly there is no sign of siezure pick-up.
I wonder why that engineering firm has "disappeared"?

And Wetdog, the spigot (if that is the right term) or collar might be a better term seems to serve the same purpose as dowels might to locate the gasket. In fact they could be considered as huge, hollow dowels.
There are no internal oilways or other passageways on a Triumph pre-unit twin cylinders area. Oil to the rockers being delivered via external pipes tapped off the engine to oil tank return oil line.
Jim.

9
British Bikes / Head Gasket blow.
« on: October 18, 2013, 12:41:06 PM »
Just over 1000 miles ago I had the barrels liners on my Triumph 5T replaced and bored back to standard.
Although I had no issues with running in I was getting a little bit unhappy with how it was settling down and with the power compared with my 5TA. Even allowing for it being a heavier machine.
When the head was removed it revealed evidence of "blow by" on the head gasket, though not actually blown. And before anyone asks, it was new and annealed before fitting in case it was old stock. And the head sequentially tightened with a torque wrench to Triumph specs.
Can anyone enlighten me as to how proud the lining tops should be above the gasket face on the cylinders? There seems to be very little "nip" on the gasket before the liners bottom (or should that be top? ;)) in the head recess.
Careful measurement leaves a gap of 0.013in when the head is placed on the barrels and the solid gasket at 0.039in is only 0.026in thicker than the gap available.
Is that sufficient for a satisfactory seal?
Checking faces as far as possible with an engineer's straight edge reveals no distortion problems.
Incidentally, I was surprised to find the thickness of the old gasket to be exactly the same as the new. Also, I must admit that I had not tried re-tightening the head.
Jim.

10
British Bikes / Re: 5TA Clutch cables.
« on: October 01, 2013, 09:33:31 AM »
Thanks Phil,
I hope to visit Stafford.
If I do I will try to find you.
Regards, Jim.

11
British Bikes / Re: 5TA Clutch cables.
« on: September 25, 2013, 09:13:55 AM »
You sound a NICE person wetdog!

However this posting might interest Rex.

I ordered "universal" cable and nipple from Trials Spares as you prompted.
The inner is visibly thicker than the cable removed, which then prompted measurement and maths.
out of curiosity.
The "universal" inner worked out as having over 11% greater cross sectional area than the failed one, which presumably, if the cable is of similar tensile strength steel, will make the cable strength 11% greater. And the soldered strength similar, or perhaps even more as the pear nipple supplied is brass, much harder and more durable than the ready made nipples on the old cable.
Hopefully you might have supplied the answer!
Thanks, Jim.

12
British Bikes / Re: 5TA Clutch cables.
« on: September 24, 2013, 10:39:29 PM »
"I only "used" cast on nipples because that is the way " .....  and after 4 fails ? heres one for you..... "an idiot never learns"  ;D being a self confesed enginner im amazed you can not solder , did you work for rover by any chance ?

I am too wise to say ANYTHING is "impossible". I have seen the "impossible" happen too many times! And the engineer I referred to could run rings around any other I have ever met. And then some.
Nor have I ever said that I could not solder. I used to TEACH people to solder!
In this modern world I did not realise the range of nipples and Bowden Cable that was still available to manufacture my own.
I readily accept that my trade was cars not bikes, and though I often manufactured choke cables etc. over a 50 years working life, there are not many motorcycle type nipples on cars.
In any case, I have still many more important things to do with my life than manufacture control cables. But then I did not expect to be buying dud cables from well recognised and supposedly reliable suppliers.
Jim.   

13
Autojumble / TA gearbox end cover wanted
« on: September 24, 2013, 08:53:43 AM »
Following advice from "Rex", I am looking for a 1964-on Triumph TA (unit) 3 ball(?) gearbox end cover for my 1959 5TA. Even just advice where to start looking would be helpful!
twolitre.

14
British Bikes / Re: 5TA Clutch cables.
« on: September 23, 2013, 04:04:39 PM »
I do have breakdown cover Rex, but I tend to be a rather independent type who sorts things out for myself whenever possible. The last time I used the cover was from Yorksire when a split link in my chain parted company. And YES the clip WAS in the correct way round. I felt rather like "for the sake of a nail ................." and a 40 mile ride in a truck when a replacement split link fitted in seconds was all that was needed seemed extreme. Especially as they were notified of the problem.

I was unaware that an alternative gearbox end-plate was available. Any pointers?
Jim.

15
British Bikes / Re: 5TA Clutch cables.
« on: September 23, 2013, 11:59:23 AM »
Thanks Rex for the link.
As I said I am not too familiar with bike engineering and I did not realise that pear nipples etc. were available , and BRASS too.
I have ordered a universal cable with a doherty style top nipple because the current cable actually has a pear nipple inside a doherty size adapter and that is where the current cable failed, though all of the others have failed at the bottom, also a pear nipple.
For wetdog:- I only "used" cast on nipples because that is the way the (ready to fit) cables I bought were manufactured. And don't forget "pride cometh before the fall"
As you both probably know, fitting a replacement cable to a 5TA means removing the gearbox end plate. No fun at the roadside even when suitable tools are carried.
Jim.

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