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Davey,
A practical and somewhat relevant question; when installing a sensor on your Ducati head bolt, do you loosen and tighten the single bolt, or go through the whole head process of loosening and tightening all the bolts.
Regards,

I don't use head bolts....they are for holding the head down and nothing else.
There are two spare tapped holes in the side of my heads so I use one for the sensor and the other for a dedicated earth return for the unit.
But for the record when I do a head bolt re-tension on the Daytona I loosen all the bolts by a third of a turn then do the full tension sequence from scratch in three passes at increasing values.

davy
 

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I think a probe attached directly to the head should be more accurate.
My curiosity about this is for several reasons; excessive heat increases the risk of detonation...bad
So is your detonation caused by excess heat or is the heat caused by detonation?
I used to suffer badly from detonation, it was starting to eat the pistons just under the plugs.
Reducing compression was a counter productive option I wasn't interested in, better, high octane fuel isn't locally available so eventually I researched octane boosters and now use Nulon Pro at the ratio of 3ml/litre which not only cured the problem enabling me to use 39.5 degrees of ignition advance but gave a substantial performance boost as well.
Gave up worrying about actual head temps but I can absolutely abuse this engine in 100 degree F ambients and the oil temp still stays within the normal acceptable range without an oil cooler which is the most important thing to me.
I do have a return filter mounted under the gearbox in the airflow so that probably helps with the oil temp to some extent.
If the oil temp was to become an issue I'd fit an alloy finned jacket around the filter as I have on my Ducati rocker oil feed filter.

davy
 

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Johntioc - I'm sorry to find this spat continuing. I did my best to leave it behind but if I'm going to be mentioned as if somehow responsible for starting it all off, I feel justified in responding.

The quote I referred to (near the top of page 2 of this thread) was perfectly in context. Derry mentioned the temperature an aero engine's aluminium head safely reaches, and I responded by expressing my doubts about your warning that exceeding 100*C would cause damage to a Triumph head's heat treatment. Realising that a cylinder head is something that is constantly heated to high temperatures and cooled right down again, it was very reasonable to raise my question, in my humble opinion. It is notable that the 4 posts following were from members expressing their own doubts about 100*C being too hot to heat a Triumph cylinder head.

My objection, as I have said all along, is not to the sharing of factual information - that's exactly what we need and want! It is to unsupported generalisations, which can easily lead to half-truths and downright inaccuracies being picked up by the trusting, and repeated elsewhere as if true, and thence becoming solidified into factoids.

Should we really never heat a Triumph cylinder head above 100*C? Well, no, but you have to take care and try not to go more than double that kind of temperature.

Should we really never use Loctite on a Triumph crankshaft sludge trap plug? Well, no, blue should be ok, but watch out for using the red stuff.

Should we really never bend the tabs on an Amal MkI stay-up float in order to adjust the float level? Well, no, but if you are going to, do so with care and bear in mind the effect that the angle of the tabs in relation to the groove in the float needle might have on how things operate in practice.

Should we never skim a Triumph twin cylinder head? Well, no, but if you do, bear in mind the effect on pushrod tube seal crush, and don't get more than absolutely necessary machined off or else expect problems in that department.

There are doubtless various other examples in existence on this and other forums of warnings to NEVER do this or that, issued without more than a passing glance at reason. In my humble opinion, such sweeping statements do nobody any service. They can actually mislead people who put blind faith in those who have reputations as 'gurus'.

As I type, I realise this might come across as challenging, but I am not meaning to simply challenge, but to ask - as I have asked previously - for any prohibitions against doing or not doing this or that, to be either qualified (ie: NOT put as blanket prohibitions in the first place) or accompanied by adequate explanation.

We are capable of understanding even quite advanced engineering concepts if they are well explained. Please don't address us as if we were idiots or children.
 

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Have you considered twin plugging your race engine?
Works well with 12:1 compression (Aries piston blanks cut to fit head), 25° advance on either a 500, 650 or 750 twin. When you start to get near 50 hp on a 500 heat starts to become a limiting factor. Especially at places like Daytona where you run nearly wide open all the time. This basic twin plug set-up provided much needed combustion control lacking with the single plug set-up. Not having the ability to dual plug one of these hemi-head combustion chambers, center plugging is a good second choice. This is a popular modification with the triple guys.

Picture of one of my early 500 squish heads:
http://www.tioc.org/500head.jpg

The blank Aries pistons used to be able to vary compression with this head. The max. you can get out of these blanks is 13:1.
http://www.tioc.org/britbike/500pistons.jpg
 

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Works well with 12:1 compression (Aries piston blanks cut to fit head), 25° advance on either a 500, 650 or 750 twin. When you start to get near 50 hp on a 500 heat starts to become a limiting factor. Especially at places like Daytona where you run nearly wide open all the time. This basic twin plug set-up provided much needed combustion control lacking with the single plug set-up. Not having the ability to dual plug one of these hemi-head combustion chambers, center plugging is a good second choice. This is a popular modification with the triple guys.

Picture of one of my early 500 squish heads:
http://www.tioc.org/500head.jpg
John, do you have a picture of the top of a twin plugged head?

davy
 

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>Have you suffered indentation on an engine you have built and run John?<
<How do you think I have collected this information??? I learn from my mistakes, at least I try.>
Is that a yes? If so what was the outcome with the recessed heads I presume you binned them and fitted new?

>It occurred to me this morning why didn't they measure any "loss" of torque and indentation with a heat treated head and add the results to their report? It seems the obvious thing to do.<
<Well, I guess they were having a bad morning and it didn't occur to them. Can I count you in to help finance the next report on Triumph heads?>
When the obvious gets left out of a report (like the missing graph) it can be for a reason, I'll let others draw their own conclusions.

<There is no water running through the bare castings when straightened. I cannot see what your point is here.>
My reasoning is that water-cooled cylinder heads expect to spend their life at 80C ish so being heated to 290C is unusual. However air-cooled heads routinely reach 250C in use so this isn't an issue for them. For instance the alloy composition for air-cooled heads may be different from water-cooled to improve their life ie a harder alloy from the start so less susceptible to the effects of softening by elevated temperatures. I hasten to add I had a quick look online for an alloy for air-cooled heads but couldn't find one.

You put forward the AA Gaskets report and asked people to read it.
 

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Discussion Starter #92 (Edited)
I don't race anymore... I'm old :eek:

Have you considered twin plugging your race engine?

davy
Oh,talking to me ?:D Yes I have thought about it. But I haven't because at this point my bike engine runs good enough to be the fastest naked "stock" frame modified production pushrod 650 bike running on any LSR track..Sometimes it's best not to mess with things that work well......;)
And to be truthful I am no expert tuner. I ask a lot of questions, I buy parts, have machine work done, and try to assemble the mess as carefully as possible. Then hours of tuning riding the Superflow Dyno..



My engine makes best power with 40 degrees total advance..Dual plugs and cutting the required spark lead to 25-30 degrees should make a better engine
 

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Truckedup;5713649 My engine makes best power with 40 degrees total advance..Dual plugs and cutting the required spark lead to 25-30 degrees should make a better engine[/QUOTE said:
Sounds about right then as my little Daytona runs at 39.5 degrees advance with the octane booster added to bring the fuel up around 102 ron.
I'm getting it to a genuine 100mph (confirmed by gps) at only 6670rpm so making reasonable power for a 500 road machine which I want to keep well under 7000rpm max.

davy
 

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From here on the sidelines, it looks as though JH is trying to give owners and amateur mechanics the sort of advice that is simple to read and follow and just might get them a happy riding experience.
Trying to do that is good. But I think I've been fairly clear in making my point that sweeping statements are not necessarily helpful, especially when perfectly polite requests for explanation are ignored (as was the case on other threads re. Loctite, stay-up floats etc). Simply obeying instructions without understanding why they were given is not a route to learning. This debate could obviously bounce back and forth indefinitely, so I'm quitting it as from now.
 

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Discussion Starter #95 (Edited)
Sounds about right then as my little Daytona runs at 39.5 degrees advance with the octane booster added to bring the fuel up around 102 ron.
I'm getting it to a genuine 100mph (confirmed by gps) at only 6670rpm so making reasonable power for a 500 road machine which I want to keep well under 7000rpm max.

davy
I use VP 107 octane leaded racing fuel,about 12 bucks a gallon in the USA.
The engine makes maximum power at 7300 rpm with a very flat torque curve because it's tuned just like a flat track engine. A hotter cam might make a few more HP at higher rpm....And more risk of breaking parts. You can win if you don't finish the sprint.....
When I was building the engine a few years ago most of the info came from John Healy and a few Aussies on Brit Bike Forum.
I found that John often speaks in generalizations on some topics that are not specifics like valve stem protrusion ,engine clearance etc.
And John told me an experienced tuner tends to tell you only one more thing that he thinks you already know...:D
Putting these two statements together, John is holding back on his speed secrets :D
Astek racing has the fastest naked frame Triumph in the country, 140 MPH ,in a different class than me and at Bonneville and El Mirage. I talk to the man about LSR racing and ask him what's inside the engine. He only tells me nothing special....:confused:
 

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I am sorry but the link I referenced in this post no longer works.
A discussion on Britbike 4 years ago:
http://www.britbike.com/forums/ubbthreads.php?ubb=showflat&Number=294629

Since this was posted I have come to learn that no matter the amount a Triumph head is warped it can be straightened cold. This should tell you something about the tensile strength of the alloy used and how it has aged in the past 50 years. And my comments reflect my, and others, experience with Triumph heads, not cylinder heads in general. I am directing my opinion to those interested in having an positive experience with their Triumph, with all its faults— not BSA or Norton or their Cessna.

In the general discussion of heads Triumph seem to be unique. 1. There isn't much to them. Turner's focus with weight carries into the execution of his head design.
2. One only has to walk around a flea market (boot sale) looking at all of the Triumph heads in their many sad states to realize their is something going on that isn't quite reflected in the text books.

Beside the indented head bolt bosses, look at the gasket surface of a T140 that used a composite head gasket with the steel folded over the edge at the combustion chamber. The surface on the head gasket surface adjacent to the steel is also recessed - the aluminum couldn't even support the localized pressure of the gasket. I would love to take all of the heads on my shelves and hardness test them but my Rockwell machine only goes down to the "C" scale and you need one that measures the "B" scale. Anyone out there have one - or a Brinell.

I don't need a hardness machine to tell me the surface would Brinell under 60 - which is considered dead soft for a cylinder head. Further examination one often sees where the head gasket surface has been machined right down into the fins increasing the chances the head will be bent even worse than before (another boat payment made by an inexperienced dealer).

Of course if the resultant increase of compression ratio doesn't cause severe detonation and piston failure before the owner gets fed up with the oil leaks from the push rod tube seals and sells the bike. Or for what appears to be an act of God an exhaust valve over heats because it can no longer find its seat in the bent head and the engine suffers catastrophic detonation. Yes, when you bend the head it upsets valve to seat alignment - go figure. That $500 three angle valve job done on a space age $250,000 Newen valve machine holding guide to seat alignment to tenths is no better than one ground on a worn out 1940 Black and Decker valve seat machine held to a couple of thousandths.

I can tell John has never worked on a bike where the owner has Red Loctited every nut, bolt and screw on the motorcycle. I only wish I could say I haven't. John, I realize you are trying to keep me honest, and that is fair, but I have come to believe that there is always a point where theory and reality collide. Some times you have to stop analyzing and find out what is happening in the real world. I think by the time he got through removing the last bolt and fixing all of the stripped threads the he would consider me a Saint for being astute, or stupid if you please, enough to point the short comings of Red Loctite and the practicality of Blue on some know problem parts of a Triumph.

And Derick what I did with the head depended on many things including the customers budget and expectations.
 

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One of the things that has come out of the bent head syndrome over the years was the misunderstanding surrounding head bolt torque. It was assumed that the 18 and 15 foot pound figures used for the copper head gasket (torque figures for the composite head gasket are about 4 lbs more)had to be wrong. The fact that the head gasket failed was not seen as a problem with the height of the push rods, but not enough head bolt torque. And if this wasn't a Triumph it would be a reasonable assumption.

Just relying on theory wasn't a bad assumption. That is until it doesn't work and you have to close the books and head to the workshop. Or, you awoke one night from a dream which put the information in the 1965 Triumph Service Bulletin about push rod tube crush together you read some years earlier with a bent head. Push rod tube leaks, failed head gaskets, bents heads, etc. have been the bane of Triumph mechanics since the first introduction of the aluminum head.

I am sure that I am not the only one that put the two together, but if they did it wasn't widely shared. Yes, most tuners will tell you one more thing that you already know to prove to you they know more than you do... a failing of the breed I guess.

John, I am not an engineer, I am a mechanic. Don't expect me to enlighten you about the vagaries of engine design and metallurgy.
 

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I am directing my opinion to those interested in having an positive experience with their Triumph, with all its faults— not BSA or Norton or their Cessna.
Oh, right, I see. You want me to have a negative experience in my Cessna now. Ta very much mate!

In case it needs saying, only joking...
 

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Sorry, got to return to this after reading the link TT posted on another thread, in which you (JH) say (on the subject of straightening Triumph heads using heat and setting them back using bolt tension against shims):-

"While slower, I prefer to use an oven. I also keep the temperature closer to 350° F to 375° F rather than the 400°F recommended. The problem is if you get the head too hot you anneal it, and that is not good. I also check the head after one hour. This requires letting it cool. 25 to 30 foot pounds is enough to reverse the bend. It takes a bit of practice! You have to be careful heating a late Triumph head, with replaceable valve seats, more than 350° F as the valve seats could drop out.

If you only have to remove .004" skimming it is an option, but don't forget to check the push rod tube O ring crush which was the cause of the original bend."

375*F is 190*C.

Its ok to skim a head if only .004" warp.

Blue Loctite sin't the same as Red.

You'd agree with all the above points, but they are quite different to the advice you published on here in the recent past. I am not trying to act like some kind of cross examiner in a court, I am merely trying to show that qualification is necessary and useful, and blanket DOs and DON'Ts are not. And the reason why is because people with every level of experience, knowledge and skill uses this forum. Some will know to take your advice with a pinch of salt, but others may not. Somebody reading to NEVER skim a Triumph head might take it literally, and waste a lot of time and worry in either a futile attempt to find somebody capable of straightening their few thou bend, of ruin it trying to do it themselves.

Similarly, somebody could read to NEVER use Loctite on a sludge trap plug, and punch the hell out of it instead, or just screw it in without Loctite or punching. Just mentioning that you mean RED Loctite, not blue, would be a big help to novices anxious to do the right thing.

This is all I've been trying to say all along really - people look up to you and the other 'gurus'. They take your advice as gospel. And in my opinion, they should be able to, unless it is given with a clear caution not to. I do not dispute your wealth of knowledge and experience and I'm absolutely certain you have a massive amount of extremely useful advice and information potentially available for us on this forum. All I ask is to please, skip the generalisations if possible, and top please follow up with qualification and / or explanation if somebody isn't clear on what or why.

Now, I really can't say any more, other than Merry Christmas John, and everyone else on here!
 

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Fair enough, and happy holidays to you also, but please go back and see who brought john healy into this on page 2 of the never ending thread. This is where someone contacted me and said that they thought that I was being quoted and that it had nothing to do with the subject which originally was about replacing crankshaft bearings or valve guides. I had absolutely no interest in this thread or plans to post to it until then.

And please don't reference my name with the use of any color Loctite on the sludge tube plug. Let alone make any suggestion that I recommend multi-punching the sludge tube plug in place. It is quite the opposite. I don't mind you quoting me but at least put the quote in context.

http://vintagebikemagazine.com/technical-articles/removing-triumph-sludge-tube/

If you are concerned that oil pressure will leak past the threads just use a little bit of thread sealant.
 
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