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(02-27-2024, 04:43 AM)m in sc_imp Wrote: piece of advice no one asked for, but its useful. Valves will tighten up , not loosen up on these bikes as miles go on (typically unless theres a mechnical failure). an early indicator of this is loss of compression on one (or more) cylinder. a down and dirty check is a warm engine compression check on all 4 cyls. if one is lower than the others beyond the allowable range, (20-30 psi i would guess) good bet that cyl needs a valve/shim adjustment. (if all else is ok). .02
@m in sc
Please correct if I say anything dumb or (partially) wrong.
If deposits built up between the valve and the valve seat, that valve can no longer return to its design position. That entails indeeed a loss in compression - gas is able to escape when the valve is in the closed position. But in this scenario the distance between valve stem end and cam has increased. The opposite of “tighten up”.
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(02-29-2024, 04:51 AM)m in sc_imp Wrote: deposits wont build up on the actual sealing surface of the seat/valve. i've never ever ever seen that unless the motor sat, unrun for many, many, many years and rust built up. even then... they will clear off after its run a bit. I spent a LOT of time in junkyards in my teens and 20s tearing into cars 
I concur.
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So what is then the main cause or process which makes vales "tighten up" over time, assuming the oil has always done it's work properly, and no knocking took place ? Are we talking about the famous seat recession, caused by the (too high ?) temperatures ? And what exactly is "seat recession" ?
I assume here that an engine like the CB1100's does not have "wild" cam profile which could also explain damage.
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Found this nice intro for all those interested ...
https://www.enginebuildermag.com/2018/03...lve-seats/
it makes me think that beyond the proverbial Honda quality there is another important factor to which we all contribute. We do more than often ride our Hondas at low(er) rpms, not the least due to age group involved, weight of the bike, but also since the engine's torque invites cruising without high revs. No wonder so little valve seat recession takes place.
So now we know the reason, why Cormanus' spreadsheet looks so clean.
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Well, that is as much or as little as I know ... a wise girl knows her limits of knowledge (and other stuff).
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... hopefully we all know our limits, but maybe that is asking too much from humanity.
If valve clearance maintenance has got one down, there are other options:
* No worries until the engine does not sound or behave (idle, start) just right. Then adjust. A lazy and passive approach.
* Acquire a legacy Honda CB inline-4 with hydraulic lifters.
* Get an electric motorcycle.
* Get a Moto Guzzi.
* Or gawd forbid, get a BMW opposed twin model.
* ... scraping the bottom: Get a single thumper.
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(03-01-2024, 10:42 PM)GoldOxide_imp Wrote: ... hopefully we all know our limits, but maybe that is asking too much from humanity.
If valve clearance maintenance has got one down, there are other options:
* No worries until the engine does not sound or behave (idle, start) just right. Then adjust. A lazy and passive approach.
* Acquire a legacy Honda CB inline-4 with hydraulic lifters.
* Get an electric motorcycle.
* Get a Moto Guzzi.
* Or gawd forbid, get a BMW opposed twin model.
* ... scraping the bottom: Get a single thumper. I strongly advise against the BMW opposed oil heads. That is going from the pan to the fire. They have a few routine wear requirements (clutch, abs, timing belt) that can be as expensive as replacing the bike.
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(03-01-2024, 10:42 PM)GoldOxide_imp Wrote: ... hopefully we all know our limits, but maybe that is asking too much from humanity.
If valve clearance maintenance has got one down, there are other options:
* No worries until the engine does not sound or behave (idle, start) just right. Then adjust. A lazy and passive approach.
* Acquire a legacy Honda CB inline-4 with hydraulic lifters.
* Get an electric motorcycle.
* Get a Moto Guzzi.
* Or gawd forbid, get a BMW opposed twin model.
* ... scraping the bottom: Get a single thumper.
I take the opposite view.
My whole life I have had no fear of taking anything apart and putting it back together.
I work in a different industry- but make a good living because of others fears of what I consider simple stuff- that a decent 12 year old could do if he was motivated enough- and can pay attention to detail.
The world would be a MUCH better place if people stopped thinking they have limits.
Not just mechanical- everything.
I just watched a video interviewing the girl that did Edge Of Tomorrow. (Great flick)
She said when she started- they put her into a program with a personal trainer.
She said she had worked out before… but once she started the program realized (paraphrasing)- “No. I’ve quickly realized I never worked out before”.
I loved watching the change in behavior of the people around me when I joined the Army.
Eye opening for many. Life changing both physical and mental for many. They will break you and reshape you.
There’s nothing whatsoever on a motorcycle that an average person can’t do, for some they just don’t want to learn, others don’t want to spend the time, so they spend the money.
I’m OK with both of those as long as they admit it. It’s when they say they can’t that I raise my eyebrow.
Want it on faster, OK. Don’t have garage space or tools, OK.
But don’t say you can’t because you are wrong.
Sent from my iPhone using Tapatalk
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(03-03-2024, 07:39 AM)PowerDubs_imp Wrote: (03-01-2024, 10:42 PM)GoldOxide_imp Wrote: ... hopefully we all know our limits, but maybe that is asking too much from humanity.
If valve clearance maintenance has got one down, there are other options:
* No worries until the engine does not sound or behave (idle, start) just right. Then adjust. A lazy and passive approach.
* Acquire a legacy Honda CB inline-4 with hydraulic lifters.
* Get an electric motorcycle.
* Get a Moto Guzzi.
* Or gawd forbid, get a BMW opposed twin model.
* ... scraping the bottom: Get a single thumper.
I take the opposite view.
My whole life I have had no fear of taking anything apart and putting it back together.
I work in a different industry- but make a good living because of others fears of what I consider simple stuff- that a decent 12 year old could do if he was motivated enough- and can pay attention to detail.
The world would be a MUCH better place if people stopped thinking they have limits.
Not just mechanical- everything.
I just watched a video interviewing the girl that did Edge Of Tomorrow. (Great flick)
She said when she started- they put her into a program with a personal trainer.
She said she had worked out before… but once she started the program realized (paraphrasing)- “No. I’ve quickly realized I never worked out before”.
I loved watching the change in behavior of the people around me when I joined the Army.
Eye opening for many. Life changing both physical and mental for many. They will break you and reshape you.
There’s nothing whatsoever on a motorcycle that an average person can’t do, for some they just don’t want to learn, others don’t want to spend the time, so they spend the money.
I’m OK with both of those as long as they admit it. It’s when they say they can’t that I raise my eyebrow.
Want it on faster, OK. Don’t have garage space or tools, OK.
But don’t say you can’t because you are wrong.
Sent from my iPhone using Tapatalk
There is famous quote from Henry Ford:
“Whether you think you can, or you think you can't--you're right.”
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PowerDubs: "My whole life I have had no fear of taking anything apart and putting it back together."
m in sc: "I didn't come out of the womb with a wrench in my hand, it's all relatively easy, just a series small tasks linked together to do.. anything, really"
What makes one person pick up a wrench, another a book? --not that they are exclusive of each other. But is it curiosity? ...encouragement to explore?... does one grow up in an environment of "try it, it'll be ok" or "don't break it, or you'll be in trouble"?
I 'credit' my 3 older brothers for hearing from my dad "don't touch"...I think the poor guy with 8 kids, financially challenged much of his life got to me, his youngest, and said "no more!" as his other sons had torn things apart, fixed this, but not that, left his tools in places he had not, and wanted his things to be...his things.
Nice thing about life is we get opportunities to change the tunes to which we dance.
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