Nevada 750 2002 gearbox input shaft cockup

Hi.
Recently become carer of my late Brother-in-law’s bike.
Not too happy with noises from clutch and/or transmission.
I’ve removed the engine & gearbox and found the clutch plate springs are loose and also damaged. The clutch rattles when shaken.
The bell housing has witness marks of some serious grinding having occurred.
New plate to be fitted of course.

Before removing the motor etc there was a whining that sounded like a straight cut racing gearbox when accelerating. The pitch changed with engine revs and not road speed. Off the gas and no noise.

The gearbox is stripped and the gears look ok.

Step one was a new clutch plate. All springs nice and tight and no play at all. :slight_smile:
The next issue is a school boy mistake. I was going to mark the flywheel before removing but for some reason I didn’t :frowning: The flywheel has 4 pips presumably for the ignition system. One of these is a double. Do you know how I should refit the flywheel? I have three positions to try and don’t want to refit and take out twice as it’s obviously going to be the last which is correct.

Is the gearbox whine how they are?

Thanks

Phil & Jane

This is a crappy video of me on the bike trying to record the noise on a ride by in the car park. I’m not normally this grumpy looking (honest)

Not sure about flywheel alignment on the small blocks but on the big blocks the marks relate to top dead center for each cylinder when viewed through the round inspection hole in the right hand side of the crank case.

I’m sure someone on here will be able to guide you better! :grinning:

Thanks for that Chris.
That’s the hole that I put my finger in when I was sat on the bike running the engine once. I found out later that there should have been a plug to stop me. Ouch!

Not 100% sure, but I bet these double pips go in relation to the crank. So - if the crank is at l/h cylinder’s TDC (10.30hrs) - pips are where the sensor is. AND THEN - check the inspection hole area(along the crankcase halves line), you should spot a mark there, stamped on a flywheel. Then you do 3/4 turn anticlockwise, the crank is at 1.30hrs, r-h cylinder TDC - and you can see another marks stamped on a flywheel, in line with crankcases split line.
Re whining, I bet either primary ratio in the gearbox - first and separate set of helical cogs taking load off the clutch - or pinion’s bearings in bevel box. Because if it happens regardless of gear engaged, you can’t blame gears, just things under permanent load.

Thats brill.
I’ll take the valve covers off and check tdc.

Gearbox. Yup that makes sense too. The initial direction reversal gears. Ill change bearing and seal and see what that does.

Cheers

Phil

Did a Google search ‘moto guzzi nevada 750 whine’, several hits, consensus seems to be some whine is normal. E.g. from wildguzzi forum: ’ Someone with more experience than me will be along, but as I said before, some whine is normal. They are straight cut, after all.’

This video is my bought brand new last October (2021) V7 850 Special, you can hear whine …

Newmarket to Kelvedon Hatch

Am I bothered? No.

Thanks Mike and thanks for your video which I think I’ve seen before on YT.

I actually like the sound of a straight cut box but Mrs Phil isn’t so keen :slight_smile:

I’ve replaced the main shaft bearing and seal and output bearing and seal or i still be doing tomorrow night.

Time will let how it goes when I refit

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Going to have to put up with then isn’t she? :grinning:

It is her bike so she does have some say but if I can’t make it quiet I’ll buy some earplugs for Christmas. : - )

Mike you are brave :roll_eyes:

We are anticipating coming to some meetings. I wonder if Mrs Phil will remember Mike’s comment… Unless I remind her of course :slight_smile:

Can you tell I’m not married? :laughing:

Teehee
Who or what sits in the side car?

Camping stuff and/or luggage mostly.