Hey everyone, thanks for watching and I hope this video helped! You might be interested in some of my other auto repair videos. You can find them by using the playlist link below. th-cam.com/play/PLHRSPnh4bEkx-mdi5iz9fX6w5DNxUnEV5.html
Direct, no BS no stupid intro no wasted time, very clear too, I'm confident now. I really appreciate this video, thank you. I wish more people could make them like this
Hey John, I wanted to let you know that I will also be using your comment during my live stream this weekend, Episode 42. Hopefully you can check it out. Thanks!
@@GettinJunkDone I was Blessed to find a true needle in a haystack on the 1100F. She even has the original exhaust with zero corrosion. I look forward to the live stream. Thanks again Bro!
Thanks for this video. I owned an 83 Nighthawk 450 from 84-91, and this was a memory jogger. The adjustment bolts are just in slightly different positions on the 750.
I have a 79 and an 81 DOHC CB750. To adjust the cam chains, you need not go to the lengths of removing the valve cover, and alternator cover - Both Chains have tensioners that are automatically adjust once loosening the adjustment bolt. For example, for the top cam chain that connects the to cams together - loosen the locknut and the 10mm. Run the engine for about 30 seconds - the chain tensioner will adjust automatedly. Now turn your engine off. Tighten the 10mm "Gently", and then the lock nut. The other tensoner is on the intake side of the engine. No Lock nut - just loosen. Start Engine. Run for 30 seconds. Stop engine. Tighten gently - You are done !
Ok thanks for clarifying for me. I'll check the later book to make sure. I do have some very slight noise with only 24k on the clock. I can only see a few threads of the front tensioner so I hope it can be fixed
nice to know it can be done! doesn't seem too difficult. I should have done this when i had the covers off before :(. Today I loosened and then turned the engine over with the starter and retightened. does this also work sometimes? I'm hoping there is a spring in there that sets the tensioner when loosened and turning
This is wrong. You dont have to take valve cover down. Only start the engine, let it warm, idle about 1000 rpm, loosen front tensioner screw for a 1/2 or 1 turn, than tighten and the same thing at the rear tensioner screw under carburator, loosen and tighten. Now the noise should be smooth.
Thanks for the video. Question ...I have an 82 750F SS and it has developed a nasty oil leak coming from the cam chain tensioner located on the front, between the exhaust pipes. I assume it's the o-ring and have one on order. The question is if I remove the tensioner bolt, can I simply reinstall? or does the bolt hold something in place and I must remove the valve cover to reinstall?Thanks in advance
Thanks,Joe. Just wondering, under normal conditions does the tensioner automatically adjust the chain? Just found a 1981 cb900c, with 14 k miles looking forward to years of fun. Keep up the good work!!!
I think it takes many thousands of miles before it needs to be reset so to speak. loosen the locking bolts and turn the engine, and retighten is my understanding
I would remove it regardless to visually verify smooth chain movement. I suppose you could go through the steps of adjusting the chain without removing the cover, then only take it off if you are hearing and odd noises for inspection, but I think it's best to remove it to have a look see before anything is tightened or loosened, just to be sure.
Hi! Thanks for this clear video. My 1979 Honda CB750 DOHC also has this rattling noise. Also the bike tends to rev-up itself while idling (like at a traffic light). When I then give it some throttle the idle lowers and then starts climbing again. Would this be the cam chain having too much slack? I tried your tip with engine running (didn't have friend around), that didn't help. So I should try the way you did. Or do you think I have a different problem? Thank you!
Gettin' Junk Done Thanks for your response. Well I already did a full carb revision, ultrasonic cleaning, carb syncing, new intake rubbers, new air filters. So I’m hoping it’s just the cam chain tensioner. I will try adjusting it by manually turning the crankshaft like you did. Will let you know if it works. Could it also be that the chain is just worn?
@@modamachina hope you've figured out your problem. I had the same issue with lean carbs and hanging idle after cleaning. I've heard there are little felt pads at either end of the throttle and choke linkages, that melt in carb cleaner. Aside from that my best guess is the ebay jets I bought with the carb rebuild kit are too small. Also syncing your carb could correct hanging idle. It's nearly scared me off of doing carb work myself. Luckily I had a spare set of carbs from the donor bike.
Mason Lundy Hi. Yes I figured it out. I adjusted the mix screws. It was running too lean on idle. It now even starts without choke. Once it’s running (at low idle) I start riding it, the bike pulls ‘till about 1/4 throttle opening. So it needs a gentle warm-up first. Once it’s at proper operating temperature it has amazing power over the entire range! Mix screws are 2 and 3/4 turns out now.
the timing on my 1980 cb900f is out,i stripped the top end and rebuilt it,lining up the dots on the camshaft sprockets parallel with the gasket,and timing t4 spot on,but when i turned the motor by hand to retension the chains the timing t4 mark is about an 8th of an inch past where it should be,the dots are still lined up parallel?,could this be a worn cam chain/tensioner?,many thanks steve
Do you know if an out of adjustment cam chain would cause nasty sounding rattle? I just got my old '82 750sc running, and it has a pretty horrendous sounding rattle (sounds like a chain) and i tested the clutch method, i heard these old bikes get play in the clutch basket and i have confirmed that is NOT the case on mine, but I have not yet done this adjustment. I suppose i will post an update tomorrow, if it quiets down after and i hope it does, but i have slight doubt in the back of my mind...
It's definitely something to look into, as I had a nasty rattle too before doing this. It's not a hard job to pull off the valve cover and verify. If you're a gambler, try using this procedure to adjust it without pulling the cover, it may just fix your problem! Thanks for watching.
I joined a cb750 forum, and as per advice i did pull the valve cover, and learned that the shop manual method was changed after several years, to this static method. My A chain tensioner has a weak spring, so i had to 'help' it take up the slack before tightening the bolts, but it did 100% cure the issue. Just loosening the bolts was not enough, it still wasnt taking out the slack until i gently pushed down on the tensioner blade, a heavy load off the mind- now have a quiet smooth running machine. on to the next step lol.
btw these are self adjusting. just just start the engine, do the front, and back screw, and done. no need to open all that stuff, just be quick so you dont burn your hands
Considering the design of the engine, I would first suspect the cam chain was out of adjustment. It's an easy enough thing to fix. I was hearing a weird knock sound that would coincide with rpm as well. Once I adjusted the chain, it went away. Hopefully yours is as simple as that. If your knock noise is still present you make have a much more severe issue. Try adjusting the chain and see what happens. Let me know.
The valve cover gasket and the rubber boots around the valve cover bolts can be reused if you are careful and they are not brittle. Both can be ordered from places online. I like to use partzilla and vintagecb750. Good luck.
moovin12 Ive never had the chance to work on that engine. I don't want to tell you something and be wrong. There must be a video or writeup available somewhere as the engine is not very rare and people have worked on them for years
Joseph Robinson yes I googled it and there's a acorn bit below the carbs you just loosen it a half turn while engine is idling and it automatically adjusts the tensioner.
I ill owed the procedure in the addendum. The addendum is direct from Honda and can be found at the cb750forum. The only difference that I know of is that I had he valve cover off. Originally the procedure was to tighten the slack out with the engine running. This was changed later on o this "static" procedure.
Sounds like the chain isn't seated corrected (somehow), you have another issue all together, or you need to try it again. Without being there to see it for myself, its hard to give you any more advice.
Hey everyone, thanks for watching and I hope this video helped! You might be interested in some of my other auto repair videos. You can find them by using the playlist link below.
th-cam.com/play/PLHRSPnh4bEkx-mdi5iz9fX6w5DNxUnEV5.html
Direct, no BS no stupid intro no wasted time, very clear too, I'm confident now. I really appreciate this video, thank you. I wish more people could make them like this
Thanks for the kind words!
I have a 83 CB1100F and I appreciate you posting this. Helped ALOT!
Glad it helped. Gotta love these old bikes. You got the BIG one!
Hey John, I wanted to let you know that I will also be using your comment during my live stream this weekend, Episode 42. Hopefully you can check it out. Thanks!
@@GettinJunkDone I was Blessed to find a true needle in a haystack on the 1100F. She even has the original exhaust with zero corrosion. I look forward to the live stream. Thanks again Bro!
Brother, you just made an intimidating job easy. I love a short video that is clear and to the point. Thanks my man!
Awesome! Glad it helped!
Just had the same issue as you, timing chain was slapping. Thanks for the video! It helped tremendously!
Thanks for this video. I owned an 83 Nighthawk 450 from 84-91, and this was a memory jogger. The adjustment bolts are just in slightly different positions on the 750.
Gotta love these old bikes.
I have a 79 and an 81 DOHC CB750. To adjust the cam chains, you need not go to the lengths of removing the valve cover, and alternator cover - Both Chains have tensioners that are automatically adjust once loosening the adjustment bolt. For example, for the top cam chain that connects the to cams together - loosen the locknut and the 10mm. Run the engine for about 30 seconds - the chain tensioner will adjust automatedly. Now turn your engine off. Tighten the 10mm "Gently", and then the lock nut. The other tensoner is on the intake side of the engine. No Lock nut - just loosen. Start Engine. Run for 30 seconds. Stop engine. Tighten gently - You are done !
Short and straight to the point. Thanks for this
Thank you soon much! Awesome quick and to the point video. Helped me out a million.
So you DO NOT really have to take the valve cover of unless you want visual confirmation?
Ok thanks for clarifying for me. I'll check the later book to make sure. I do have some very slight noise with only 24k on the clock. I can only see a few threads of the front tensioner so I hope it can be fixed
finally a quick easy no bs vid. Thanks man!!!
Great video just what i was looking for. I have a 82 cb750c, keep posting more about these hondas!
Thank you for this, I appreciate the video!
I'm picking up an 82 cb750 from a dealer on friday. It sounded healthy but I'm going to do this just for safe measure
Not a bad idea. All the normal items too...oil, brakes, lube the cables, ect.
if your bike is together you can just do this while the bike idles
nice to know it can be done! doesn't seem too difficult. I should have done this when i had the covers off before :(. Today I loosened and then turned the engine over with the starter and retightened. does this also work sometimes? I'm hoping there is a spring in there that sets the tensioner when loosened and turning
This is wrong. You dont have to take valve cover down. Only start the engine, let it warm, idle about 1000 rpm, loosen front tensioner screw for a 1/2 or 1 turn, than tighten and the same thing at the rear tensioner screw under carburator, loosen and tighten. Now the noise should be smooth.
Thanks for the video. Question ...I have an 82 750F SS and it has developed a nasty oil leak coming from the cam chain tensioner located on the front, between the exhaust pipes. I assume it's the o-ring and have one on order. The question is if I remove the tensioner bolt, can I simply reinstall? or does the bolt hold something in place and I must remove the valve cover to reinstall?Thanks in advance
why do you take the valve cover off? Thanks
thank you for this video.. i have a cb900c and the chain is a little noisey when cold..
Glad it helped. I couldn't find a video myself, so once I figured out how easy it was, I threw on up. Thanks for watching.
Any recommendations for those of us who stripped the front bolt?
Hi, very good video, does that apply to 1984 CBX750F too?
Thanks,Joe. Just wondering, under normal conditions does the tensioner automatically adjust the chain? Just found a 1981 cb900c, with 14 k miles looking forward to years of fun. Keep up the good work!!!
That is my understanding, yes. Love these bikes! Keep that thing on the road!
I think it takes many thousands of miles before it needs to be reset so to speak. loosen the locking bolts and turn the engine, and retighten is my understanding
Can i completely remove the front bolt to replace the O ring at the bottom?
Great video! Is the necessity of removing the cam cover only for inspection of the chain tension?
I would remove it regardless to visually verify smooth chain movement. I suppose you could go through the steps of adjusting the chain without removing the cover, then only take it off if you are hearing and odd noises for inspection, but I think it's best to remove it to have a look see before anything is tightened or loosened, just to be sure.
Yeah. It's a good idea. Thank you very much for helping!
Does it not do anythinf if the crank isnt turning?
Hi! Thanks for this clear video. My 1979 Honda CB750 DOHC also has this rattling noise. Also the bike tends to rev-up itself while idling (like at a traffic light). When I then give it some throttle the idle lowers and then starts climbing again. Would this be the cam chain having too much slack?
I tried your tip with engine running (didn't have friend around), that didn't help. So I should try the way you did. Or do you think I have a different problem? Thank you!
I would double check the chain, but may also be an issue with your carbs. That's what's popping into my head at the moment from your description.
Gettin' Junk Done Thanks for your response. Well I already did a full carb revision, ultrasonic cleaning, carb syncing, new intake rubbers, new air filters. So I’m hoping it’s just the cam chain tensioner. I will try adjusting it by manually turning the crankshaft like you did. Will let you know if it works. Could it also be that the chain is just worn?
@@modamachina hope you've figured out your problem. I had the same issue with lean carbs and hanging idle after cleaning. I've heard there are little felt pads at either end of the throttle and choke linkages, that melt in carb cleaner. Aside from that my best guess is the ebay jets I bought with the carb rebuild kit are too small. Also syncing your carb could correct hanging idle. It's nearly scared me off of doing carb work myself. Luckily I had a spare set of carbs from the donor bike.
Mason Lundy Hi. Yes I figured it out. I adjusted the mix screws. It was running too lean on idle. It now even starts without choke. Once it’s running (at low idle) I start riding it, the bike pulls ‘till about 1/4 throttle opening. So it needs a gentle warm-up first. Once it’s at proper operating temperature it has amazing power over the entire range! Mix screws are 2 and 3/4 turns out now.
Great, is it the same for the primary chain?
Do you have to drain the oil?
the timing on my 1980 cb900f is out,i stripped the top end and rebuilt it,lining up the dots on the camshaft sprockets parallel with the gasket,and timing t4 spot on,but when i turned the motor by hand to retension the chains the timing t4 mark is about an 8th of an inch past where it should be,the dots are still lined up parallel?,could this be a worn cam chain/tensioner?,many thanks steve
Do you know if an out of adjustment cam chain would cause nasty sounding rattle? I just got my old '82 750sc running, and it has a pretty horrendous sounding rattle (sounds like a chain) and i tested the clutch method, i heard these old bikes get play in the clutch basket and i have confirmed that is NOT the case on mine, but I have not yet done this adjustment. I suppose i will post an update tomorrow, if it quiets down after and i hope it does, but i have slight doubt in the back of my mind...
It's definitely something to look into, as I had a nasty rattle too before doing this. It's not a hard job to pull off the valve cover and verify. If you're a gambler, try using this procedure to adjust it without pulling the cover, it may just fix your problem! Thanks for watching.
I joined a cb750 forum, and as per advice i did pull the valve cover, and learned that the shop manual method was changed after several years, to this static method. My A chain tensioner has a weak spring, so i had to 'help' it take up the slack before tightening the bolts, but it did 100% cure the issue. Just loosening the bolts was not enough, it still wasnt taking out the slack until i gently pushed down on the tensioner blade, a heavy load off the mind- now have a quiet smooth running machine. on to the next step lol.
+Pat Foster that's great'. Glad it finally got figured out. I'll have to keep all of that in mind if I ever come across the same issue. Thanks!
Thanks good video.
Thanks for watching!
Is it the same for the 550s from 83?
btw these are self adjusting. just just start the engine, do the front, and back screw, and done. no need to open all that stuff, just be quick so you dont burn your hands
How exactly do you adjust the rear nuts?
Using a wrench or a socket. Reach in there and turn them like in the video.
I have 1980honda cb750c dohc and I hear a knocking noise. Can you explain what you were hearing. Mine gets louder as I would put a load on it
Considering the design of the engine, I would first suspect the cam chain was out of adjustment. It's an easy enough thing to fix. I was hearing a weird knock sound that would coincide with rpm as well. Once I adjusted the chain, it went away. Hopefully yours is as simple as that. If your knock noise is still present you make have a much more severe issue. Try adjusting the chain and see what happens. Let me know.
Joseph Robinson thank you will do. Do I need to replace the gaskets if they are rubber?
The valve cover gasket and the rubber boots around the valve cover bolts can be reused if you are careful and they are not brittle. Both can be ordered from places online. I like to use partzilla and vintagecb750. Good luck.
do you know how to adjust a cb450sc 1982 engine ?
moovin12 Ive never had the chance to work on that engine. I don't want to tell you something and be wrong. There must be a video or writeup available somewhere as the engine is not very rare and people have worked on them for years
Joseph Robinson yes I googled it and there's a acorn bit below the carbs you just loosen it a half turn while engine is idling and it automatically adjusts the tensioner.
This is different then the oem manual.
I'm not sure I would trust this
I ill owed the procedure in the addendum. The addendum is direct from Honda and can be found at the cb750forum. The only difference that I know of is that I had he valve cover off.
Originally the procedure was to tighten the slack out with the engine running. This was changed later on o this "static" procedure.
I followed*
Boy. I tried this, and now my bike rattles even more. I should have never touched it.
Sounds like the chain isn't seated corrected (somehow), you have another issue all together, or you need to try it again. Without being there to see it for myself, its hard to give you any more advice.