TS1 bore wear
To me it all seems a bit backwards with a very hard surface lining and soft heat transporting material if you can't stabilise the heat with a thermostat. Materials will start moving when loosing or gaining heat. All to their own but when I installed my first EGT gauge some 13 years ago on my Ts1 I discovered how much it goes up and down in temperature. Would not a massive piece of cast be better in the long run if set up right, just saying.
Hi guys EGT is a bit irrelavant as exhaust gas temps go up and down with several different circumstances......retarded timing will make an EGT read extremely hot but it does not mean your motor is getting hot just the flame still burning when it gets chucked out the exhaust. Advanced timing will make an EGT run cooler but it does not mean its good for your motor.
We all have differing opinions between cast and ally and thats fine i am not going to try and convince anyone. My money is on ally barrel every time. I have holed a piston due to my own mistake on jetting with an ally barrel but i have never, ever seized one. They do seize but generally due to a dome being created in the piston and then molten ally getting between the piston and bore but they rarely seize like iron barrels do. They have more of a tolerance for overheating however when detonation etc starts to cause damage they will fail of course.
Its pretty simple....ally barrels allow you to run tighter piston to bore clearances resulting in smoother engine and more power. Also just think .....what is your piston made of....ally.....it expands far quicker than than iron resulting in more chance of seizure and having to run looser tolerances.....that is fact. However if you seize an iron barrel its just clean up the piston and rebore or hone. I think that a correctly set motor should not seize at all but its just my opinion.
So it is horses for courses but they are my basic reasons for running ally barrels.
Its not gospel.....just my opinion.
We all have differing opinions between cast and ally and thats fine i am not going to try and convince anyone. My money is on ally barrel every time. I have holed a piston due to my own mistake on jetting with an ally barrel but i have never, ever seized one. They do seize but generally due to a dome being created in the piston and then molten ally getting between the piston and bore but they rarely seize like iron barrels do. They have more of a tolerance for overheating however when detonation etc starts to cause damage they will fail of course.
Its pretty simple....ally barrels allow you to run tighter piston to bore clearances resulting in smoother engine and more power. Also just think .....what is your piston made of....ally.....it expands far quicker than than iron resulting in more chance of seizure and having to run looser tolerances.....that is fact. However if you seize an iron barrel its just clean up the piston and rebore or hone. I think that a correctly set motor should not seize at all but its just my opinion.
So it is horses for courses but they are my basic reasons for running ally barrels.
Its not gospel.....just my opinion.
regarding tighter clearances on nikasil compared to cast,, a bigger clearance is used on cast iron because, as you say, the piston expands more than the iron which in turn means the RUNNING clearance is tighter than the cold clearance!
As you are saying its a bit irrelevant but gave me a clue back then how much heat goes up and down, the heat comes from somewhere right. Now there's all types of fancy pancy multi gauges for CHT and EGT and my novice theory's proved to be somewhat right, just saying.
Fair point Eden, that's why I think its down to personal preference and experiences.
Hi Slangen, I think CHT is more relevant to how hot your barrel/head is getting as it measures the actual heat of your head where as EGT gives you more or less real time feed back on the heat of the exhaust gases. EGT reacts quicker but its measuring the gases rather than heat build up in the head/barrel where as CHT will tell you how hot your actual head/barrel is getting but reacts slower. Ideal situation is to have both readouts.
Your right in what you say, that a barrel will expand and contract as it gets hotter or colder but this is why an ally barrel is considered by some to be better as it dissipates the heat quicker.
Hi Slangen, I think CHT is more relevant to how hot your barrel/head is getting as it measures the actual heat of your head where as EGT gives you more or less real time feed back on the heat of the exhaust gases. EGT reacts quicker but its measuring the gases rather than heat build up in the head/barrel where as CHT will tell you how hot your actual head/barrel is getting but reacts slower. Ideal situation is to have both readouts.
Your right in what you say, that a barrel will expand and contract as it gets hotter or colder but this is why an ally barrel is considered by some to be better as it dissipates the heat quicker.
Yep it sure is Nelson, it's what I had back then. As you say it's up to personal preferences and I'm sure it depends on what your riding style is. Nowadays I like to ride long and fast and I try to convince myself with that type if riding it is better with a big lump that keeps an even temp, but I'm sure there are adults here that knows better.
Iron bore, Ali jaket, best of both worlds ?
win or lose have a booze
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Adam_Winstone
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Alloy jacket with soft iron liner... worn out as quickly as it is run in!
Some of these combo barrels are excellent, others are a short-lived folly. Even having an iron liner put into a previously plated barrel can be soft and not provide the solution that was hoped for... other times it can be the best of both worlds.
I agree that there is a time and place for either (or both) and I understand the bias of some people, however, I also get the feeling that some people play down one option just to promote their own bias (cough, cough, Eden... no, only joking!), rather than give an objective portrayal of each. No, I was totally joking with the name mentioned and respect individuals with a strong passion for either but do sometimes feel that shops 'talk down' one option or t'other just to shift what they have sitting on their shelves
As long as it is a Lambretta casing, I don't care which top end goes on it! (kidding about that too)
Adam
Some of these combo barrels are excellent, others are a short-lived folly. Even having an iron liner put into a previously plated barrel can be soft and not provide the solution that was hoped for... other times it can be the best of both worlds.
I agree that there is a time and place for either (or both) and I understand the bias of some people, however, I also get the feeling that some people play down one option just to promote their own bias (cough, cough, Eden... no, only joking!), rather than give an objective portrayal of each. No, I was totally joking with the name mentioned and respect individuals with a strong passion for either but do sometimes feel that shops 'talk down' one option or t'other just to shift what they have sitting on their shelves
As long as it is a Lambretta casing, I don't care which top end goes on it! (kidding about that too)
Adam
im happy if everyone uses ali kits because it means my cast iron barrel collection keeps growing
tbh I only go on about cast iron barrels because they have served me so well for the last 33 years. Ive never felt the need to go down the ali barrel route even though nearly everyone I ride with either still use them or have used them in the past.
Some people used to take the p155 about my STONE AGE tunes on STONE AGE barrels, that tends not to happen so often now, I wonder why
