Gearbox whine and clutch rattle

[royhall]

Hi all. Just bought an F2 sohc that's been standing for about 4 years. Wasn't running when I bought it so did not get the chance of a test ride (price was very good so took a chance). Been through it all and it now runs very well, in fact will pull to the redline without missing a beat. Now the problem I could use advice on: the big one is when riding it there is a noticeable whine from the gearbox. Never having owned one before could somebody let me know if this is normal or maybe a gearbox bearing or something. It goes into all the gears really well, up and down the box and finds neutral okay. The other noise is the clutch at tickover. It is very rattly although it is adjusted correctly, and work well. These noises are unnerving and I wonder should I be using the bike as it may be causing damage. Any help would be appreciated. Cheers.

[tom400f]

All of these Honda fours will suffer some "rattle" when idling in neutral. How much will depend on how worn the cush rubbers in the clutch are and how well balanced your carbs are. Of itself it's not much to worry about but hard to say as it's all down to degree.

They do whine as well, (well mine is a 400 and it certainly does). You don't say which gear so I assume all of them (mine is loudest in 2nd, especially on the overrun).

If you say what work you have done, mileage and so on, there would be more to go on.

[royhall]

Thanks for the reply. Done the full thing on the bike ie. carb clean and rebuild (full apart and ultrasonic), oil change and filter, air filter and new filter trumpets, new plugs/points/condensers, set the tappets, checked and set cam chain tensioner, strobed the ignition/checked advance, balanced the carbs/set slow running mixtures with shop tacho, and many more check and repairs. Mileage is about 29000 miles. The whine is in all gears, but more noticeable in first and second. Not too worried about the clutch just yet as I haven't pulled it out for a check over, will try to do that next weekend. The bike is an F2 and I suspect it may have K series plates in it. If it has could be an easy fix will see at weekend. Much more concerned about the gearbox thing though as that could be an engine strip jobby. Not what you want just coming into summer. Cheers.

[Green1]

Totally agree with Tom my 750k1 is incredibly rattly from cold everyone that is new to these worries about the clutch rattle
and the cam chain sounds like its chewing the head even when adjusted properly.
If theirs nothing in the old oil don't worry about it. 

Mick

[UK Pete]

All sounds like the usual sohc noises, i dont think you have much to worry about
pete

[royhall]

Thanks for that. The oil that came out of it was jet black so I ran it through a filter paper to check for glitter, found nothing in the oil or the oil filter. When I pull in the clutch lever the clutch noise stops almost completely and no other noises from the engine are apparant (not even cam chain strangely). Was a whole lot more concerned about that gearbox whine. Your correct about me being new to Honda's, have spent all my time with Kawasaki Zeds, and they are the quietest clutches ever made so it was a bit of a shock. How loud should the transmission noise be? Thanks for your help.

[steff750]

  clutch rattle is normal on Hondas if it goes when the clutch is disengaged, then it only needs the carbs balanced even then it may not go away completely
Honda gearboxs are very notchy and you need to be real postitive with gear changes( id say Suzuki best gearboxs on the planet) but unless the whine is really bad I would run it a while longer to get used to its quirks are you sure its gearbox and not wheel bearings id say its final drive bearings if anything, you will need to check it out to be on the safe side gearbox seizure is not nice

[royhall]

Yeah fairly sure its gearbox, its not a really noisy whine just kinda there if you know what I mean. Nothing seamed amiss with the cycle parts when I went through it all. Have had both wheels off the ground and done a fair bit of pushing and pulling looking for worn bearings/bushes. Only thing appearing loose were the head bearings and I have sorted that. Will check out your suggestion though just to make double sure. Carbs are carefully balanced, took ages over it and got it almost bob on. Didn't change the clutch noise at all. Clutch noise does calm down some when its hot. Think I will pull it next weekend just to make sure, talking to the previous owner he didn't fill me with confidence about his knowledge or abilities. Thanks all.

[Trigger]

If the bike has been sitting about for years you can get rust on the bearings because of no oil running. This can give a bad sound. Change the oil for the first 500 miles just to flush out anything that should not be in there.  As everyone has said, run it for a while to see what happens. I always fit a magnetic plug to all the CB engines i do. If it gives a big clunk as you put it into gear. That is also normal on these old girls.

[royhall]

Okay thanks for all the replies. Will check clutch this weekend then give it a run for a few months. See if anything happens. Many thanks.

[Bitsa (Ralph Wright - RIP)]

Here you go the lastest and best way of getting her the quietest
Works great for me when them 4 guages are all lined up and all done up release the special tool and she dont half sound that bad anymore.A lot less of that lumpy sounding ready to stall noise
Cheers
Bitsa