Watch, you might learn something.
Seasoned HDF Member
Joined: Feb 2008
Posts: 23,001
Likes: 11,441
So riding in the rain is a good thing. I was right all these years.
Seasoned HDF Member
Joined: Aug 2008
Posts: 5,071
Likes: 1,006
a gasoline or really any fossil fuel engine has a very narrow sweet zone where it is most efficient. the concept of blowing out the carbon is an ole wife's tale.
nothing wrong with using the entire rpm range but that also goes back to design, you wouldn't want to use a nascar in ny city traffic.
just spritzing water into the manifold will not do the trick, it is a long term process, i used water injection on my dodge 440, really makes a diff.
the ole hd two strokes were notorious for filling up the exhaust port to the point the engine would not rev, but look how it was mixed, a cup attached to the gas cap. i seen guys use plain ole engine oil.
never had issues with the more modern designs that used oil injection. that does not mean there was not fouled plug. i find that the carbon tacked plug was from a rapid cool down and the power on which burned the oil on a wet plug.
i really like my suzuki system. the oil was pumped to the crank bearings and up to the wrist pin bearing and the sling off mixed with in coming fuel. the cowpie and you-ma-make it inject in the carb port more prone to carbon tack.
nothing wrong with using the entire rpm range but that also goes back to design, you wouldn't want to use a nascar in ny city traffic.
just spritzing water into the manifold will not do the trick, it is a long term process, i used water injection on my dodge 440, really makes a diff.
the ole hd two strokes were notorious for filling up the exhaust port to the point the engine would not rev, but look how it was mixed, a cup attached to the gas cap. i seen guys use plain ole engine oil.
never had issues with the more modern designs that used oil injection. that does not mean there was not fouled plug. i find that the carbon tacked plug was from a rapid cool down and the power on which burned the oil on a wet plug.
i really like my suzuki system. the oil was pumped to the crank bearings and up to the wrist pin bearing and the sling off mixed with in coming fuel. the cowpie and you-ma-make it inject in the carb port more prone to carbon tack.
Seasoned HDF Member
Joined: Dec 2005
Posts: 19,925
Likes: 8,027
From: poway
I would disagree with this.. A lot will have to do with jetting / efi tuning. While many complained about the removal of lead from fuel, it was good thing. Spark plugs lasted a lot longer.
In 1978, I was a service manager in a Honda shop. Long time customer brought in a GL1000 for service. A mechanic got the job and proceeded with the work.. Upon completion, he took it out for a test ride and bike ran like crap.. Brought it back in tried reving it up a little and it sounded like ****. Ran a compression check and got like 80 psi on all the cylinders. Recommended a valve job to the customer. Bike was low miles, less than 20K... I told the guy the bad news and he left.
He came back a few days later, told me he'd taken the bike to another shop and they'd check the compression. It was 120 psi.. At that time I new what was wrong and told him to leave it.. I personally took the bike out on the freeway, and ran it at the 55 mph speed limit in first gear, 8500 rpm right at the red line. The bike almost stopped running it was so choked up but after a couple miles it cleared up. I spent some time running it through the gears hard and it start running good.. Brought it back to the shop, had a mechanic replace the plugs and check the valve adjustment. Compression was up to 140 (spec). After that the motor ran fine..
When the customer arrived to pick up the bike, I found out that he never ran the motor above 4000 rpm.. Told him to take to the redline occasionally and it would run a lot better.
FWIW, the original mechanic did screw up.. It was good that the customer that had been using the shop I was working at for years came back and told us something was wrong. One of the reason why it's good to take the bike back to shop if you have issues with the work. **** gets missed.. Most of the time the customer is better off and so is the shop..
In 1978, I was a service manager in a Honda shop. Long time customer brought in a GL1000 for service. A mechanic got the job and proceeded with the work.. Upon completion, he took it out for a test ride and bike ran like crap.. Brought it back in tried reving it up a little and it sounded like ****. Ran a compression check and got like 80 psi on all the cylinders. Recommended a valve job to the customer. Bike was low miles, less than 20K... I told the guy the bad news and he left.
He came back a few days later, told me he'd taken the bike to another shop and they'd check the compression. It was 120 psi.. At that time I new what was wrong and told him to leave it.. I personally took the bike out on the freeway, and ran it at the 55 mph speed limit in first gear, 8500 rpm right at the red line. The bike almost stopped running it was so choked up but after a couple miles it cleared up. I spent some time running it through the gears hard and it start running good.. Brought it back to the shop, had a mechanic replace the plugs and check the valve adjustment. Compression was up to 140 (spec). After that the motor ran fine..
When the customer arrived to pick up the bike, I found out that he never ran the motor above 4000 rpm.. Told him to take to the redline occasionally and it would run a lot better.
FWIW, the original mechanic did screw up.. It was good that the customer that had been using the shop I was working at for years came back and told us something was wrong. One of the reason why it's good to take the bike back to shop if you have issues with the work. **** gets missed.. Most of the time the customer is better off and so is the shop..
Seasoned HDF Member
Joined: Aug 2008
Posts: 5,071
Likes: 1,006
on old crappy design i do agree that engines can carbon up. oil control was just about non existent and oil quality not so great. most deposits were not from the fuel but the additives. throw in bad c/c vent systems or over taxed systems played an important part. to blow carbon off an engine would require more that a sprint or two.
unlike an electric motor an engine has a power curve and said sweet spot where the burn is near complete. back in the olden days, mfg's set the common cruise for that spot, aka 3k range.
with today's electronics, i can pull an 11,500# fifth wheel with a 5.3 and a 3.373 65 mph and not break 2k.
the science is not behind that concept.
i did some goodwrench work when the oilfield was down and we did get carboned out engines come in the shop. gm used to make a cleaner for that and it would gag a maggot when it burned through the engine, had to do it in an open field, no one would survive in the shop. matter of fact, the tailpipe emissions would kill the grass. epa killed that chemical. you could peg that car at 100mphfrom new orleans to chicago and nowhere near clean out the carbon. how hot must a piston get to burn off carbon!
the water injection works for sure.
unlike an electric motor an engine has a power curve and said sweet spot where the burn is near complete. back in the olden days, mfg's set the common cruise for that spot, aka 3k range.
with today's electronics, i can pull an 11,500# fifth wheel with a 5.3 and a 3.373 65 mph and not break 2k.
the science is not behind that concept.
i did some goodwrench work when the oilfield was down and we did get carboned out engines come in the shop. gm used to make a cleaner for that and it would gag a maggot when it burned through the engine, had to do it in an open field, no one would survive in the shop. matter of fact, the tailpipe emissions would kill the grass. epa killed that chemical. you could peg that car at 100mphfrom new orleans to chicago and nowhere near clean out the carbon. how hot must a piston get to burn off carbon!
the water injection works for sure.
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Seasoned HDF Member
Joined: Dec 2005
Posts: 19,925
Likes: 8,027
From: poway
on old crappy design i do agree that engines can carbon up. oil control was just about non existent and oil quality not so great. most deposits were not from the fuel but the additives. throw in bad c/c vent systems or over taxed systems played an important part. to blow carbon off an engine would require more that a sprint or two.
unlike an electric motor an engine has a power curve and said sweet spot where the burn is near complete. back in the olden days, mfg's set the common cruise for that spot, aka 3k range.
with today's electronics, i can pull an 11,500# fifth wheel with a 5.3 and a 3.373 65 mph and not break 2k.
the science is not behind that concept.
i did some goodwrench work when the oilfield was down and we did get carboned out engines come in the shop. gm used to make a cleaner for that and it would gag a maggot when it burned through the engine, had to do it in an open field, no one would survive in the shop. matter of fact, the tailpipe emissions would kill the grass. epa killed that chemical. you could peg that car at 100mphfrom new orleans to chicago and nowhere near clean out the carbon. how hot must a piston get to burn off carbon!
the water injection works for sure.
unlike an electric motor an engine has a power curve and said sweet spot where the burn is near complete. back in the olden days, mfg's set the common cruise for that spot, aka 3k range.
with today's electronics, i can pull an 11,500# fifth wheel with a 5.3 and a 3.373 65 mph and not break 2k.
the science is not behind that concept.
i did some goodwrench work when the oilfield was down and we did get carboned out engines come in the shop. gm used to make a cleaner for that and it would gag a maggot when it burned through the engine, had to do it in an open field, no one would survive in the shop. matter of fact, the tailpipe emissions would kill the grass. epa killed that chemical. you could peg that car at 100mphfrom new orleans to chicago and nowhere near clean out the carbon. how hot must a piston get to burn off carbon!
the water injection works for sure.
FWIW I own a 78 cb750.. Redline is at 8500. Motor spins at 6 grand 30-40 miles no issues..
I'd like to you you take your rig up the interstate 8 headed west from Ocotillo to Jacumba at 65 and keep the Rs below 2K..
Seasoned HDF Member
Joined: Aug 2008
Posts: 5,071
Likes: 1,006
hummmmm?????
still no scientific evidence
2 smokes of what left hander's
yep, been up grades and i do not push the engine, i set it around 3k and let it do its thing, yep, i may be slow but i am ahead of you sign on the rear. AND YET, some redneck will pass in a blind curve and no guard rail and endanger everyone involved.
i made a huge mistake and over built a honda 305, redline 12,500 and could stay with your 750 up to 90mph when she topped out. i could get about 3 runs if i was lucky before the piston rings shattered and blew blue smoke all over the place.
was such a pain that i developed a way to remove the top end with engine in frame. thank goodness for the trap door on the cam chain.
no one here is debating where or not to use the full range of rpm, it is about where it actually removes carbon. there are TOOOOOO many variables and engine load plays an important role.
my xls stock was 5.4k @ 120 but jump ahead 7.5k and i do not know, clock runs out at 120mph. i run int'l gearing and at 6k she is running about 140 and squirrelly as he$$.
this is the projected info but have to factor in many things to get actual. it is a real hoot, surprises some rice and definitely cagers.
still no scientific evidence
2 smokes of what left hander's
yep, been up grades and i do not push the engine, i set it around 3k and let it do its thing, yep, i may be slow but i am ahead of you sign on the rear. AND YET, some redneck will pass in a blind curve and no guard rail and endanger everyone involved.
i made a huge mistake and over built a honda 305, redline 12,500 and could stay with your 750 up to 90mph when she topped out. i could get about 3 runs if i was lucky before the piston rings shattered and blew blue smoke all over the place.
was such a pain that i developed a way to remove the top end with engine in frame. thank goodness for the trap door on the cam chain.
no one here is debating where or not to use the full range of rpm, it is about where it actually removes carbon. there are TOOOOOO many variables and engine load plays an important role.
my xls stock was 5.4k @ 120 but jump ahead 7.5k and i do not know, clock runs out at 120mph. i run int'l gearing and at 6k she is running about 140 and squirrelly as he$$.
this is the projected info but have to factor in many things to get actual. it is a real hoot, surprises some rice and definitely cagers.