Primary Gear Noise and Solution
Posted November 27, 2000 - 01:27 PM
So, the questions are:
1.) How difficult was the fix? (Scale from 1-10, 10 being hardest)
2.) Did you have to remove the clutch basket?
3.) Did you have to remove the entire right side cover to inlcude water pump and filter or just the clutch cover?
4.) How long did it take?
5.) Should this be a warranty item?
6.) Do you have to replace any gaskets?
7.) Should you replace any parts while you are already in there?
You see where I'm going? I have limited time so if it's pretty easy and does not require the clutch basket to come off I'll take it on myself. If it's pretty much a bitch, I'll have my buddy at the local shop do it. In my opinion it should be a warranty item though so the shop should do it for free. Please be specific as possible in your response.
Roostn in Denver
Posted November 27, 2000 - 01:58 PM
Also, I have heard of several keys needing replaced. Is the key in question item 9?
These are on two separate gears so which one is the culprit? I'm assuming you are talking about item 12 as the CB gear and item 8 being the Primary Gear.
What I am hearing is there is a bolt that holds on item 8 and it comes loose resulting in the rattling noise.
Several of you have had the nut (item 16) come loose which takes out its key and results in a similar noise.
Am I on the right track?
Roostn in Denver
Posted November 27, 2000 - 03:41 PM
Nut and washer are # 2 & # 3, respectively, in this picture
Item 12 is the CB gear but it is held on w/ splines and doesn’t have the play problem, the gear that drives it does (the CB drive gear), it is # 8 in your picture (but don’t appear in the pic I linked above). So # 8 in your pic is the one you need to check for play, and the main gear retaining nut and washer are (#2 & 3 in above pic) what you need to check for tightness.
There are only two keys on the whole bike, both on the crank, one is woodruff on the flywheel and the other is the straight key that secures the CB drive gear.
Now you should be on the right track.
Hope this helps!
Posted November 28, 2000 - 11:05 AM
Originally posted by ART:
Does the clutch have to come off to get to the C.B. and primary gear?
You can check the retaining nut for tightness, visually inspect the lock washer and check the CB drive gear for play with the clutch on. But since the main drive gear drives the large gear behind the basket this needs to come off if either gear on the main (crank) shaft is to be removed.
Posted November 28, 2000 - 11:07 AM
I guess I'll have to look at my manual tonight before I get any real data. I do know the oil, and water must be drained and the big cover must be removed in order to get in there and change anything.
Hopefully someone who has actually done this before can get on and add some clarity.
ROOSTN in Denver
Posted November 28, 2000 - 02:58 PM
Sorry to have only muddled the picture for you, but I have done this before (twice). I’ll try my best to make some sense of the mess I’ve made…
Item # 1 is the main gear which drives the clutch and tranny. Item # 8 is the CB drive gear, or the gear on the crankshaft that drives the counterbalancer. This gear rides on the crankshaft behind (or inside) the main gear. The main gear is held in place with splines. The CB drive gear is held in place with a straight key (but this is changed to splines also for ’01. Gee, I wonder why? ).
To remove right cover:
1) Drain water and oil
2) Remove brake pedal (don’t forget to remove retaining pin in the end of the bolt before unthreading) and spring.
3) Remove kickstarter
4) Remove water pump cover, secure it out of the way with a zip tie or safety wire.
5) Remove oil supply line, dowel and o-ring. This is at bottom of cover below filter housing.
6) Remove chrome oil delivery pipe at pressure end, this is a banjo bolt w/ two copper washers on top of case next to cylinder just above filter housing. You can pry the pipe up a bit to get the bottom washer out.
7) Remove oil filter cover and filter
8) Remove all case bolts
9) Remove ONLY two clutch cover bolts at forward, top side of cover (these also secure main cover).
10) Remove cover gently to save the gasket.
There are two, solid and very small dowels in the water pump cover. Don’t lose them. There are two, hollow, larger (~ 10 mm) dowels in case or cover, bottom right and top left. There is also a dowel and o-ring that go from the filter housing (in the cover) to the oil pump (in the case), if this dowel and o-ring came out with the cover remove and insert them into the pump so you don’t lose them (running the motor w/out this dowel & o-ring would be disastrous).
I just leave the bolts in their holes to ease reinstall, but the manual is pretty good at pointing out which length fastener goes into which holes if you want to do it that way.
To the right of the clutch you will see the crankshaft, mounted on it is a nut, lockwasher (w/ bent over tab), main gear, CB drive gear (in that order front to back) and straight key that holds it. Immediately to the right of this is the CB shaft which has one gear (with a bolted on counterweight) secured by splines and also held on with a nut and lockwasher.
What creates the racket is a rounded straight key under the CB drive gear which allows the counterbalancer to oscillate to and fro relative to the crankshaft (instead of staying “in phase.”). A rounded key is usually accompanied by a loose main gear retaining nut but the opposite may not always be true. If, once you have the cover off, you can rotate the CB drive gear, even slightly, w/out the crank moving then it is time to take off the clutch, remove the two gears and replace the key. If this happens make sure you inspect the CB drive gear, its keyway and the keyway in the shaft as well as replace the lock washer, it doesn’t clear the basket by a whole lot and you don’t want an overly bent washer making contact here.
When reinstalling the gears make sure the punch marks on the CB gear and CB drive gear align and make sure you bend the lock washer tab flush against the nut. When reinstalling the cover align the kickstarter hole and gently apply pressure while rotating the water pump impeller to align it with the notch in the counterbalancer. You shouldn’t feel much resistance.
Or you can get your dealer to do this for you and, if this is the case, be thankful you have a competent mechanic at your disposal whom you can trust because not everybody enjoys this convenience
I hope this helps (I’m tryin’ anyway…).
[This message has been edited by Hick (edited 11-28-2000).]
Posted November 28, 2000 - 04:58 PM
Again, thanks for the great posting, that REALLY cleared things up!
ROOSTN in Denver
Posted November 28, 2000 - 05:09 PM
Posted November 28, 2000 - 06:24 PM
When you reassemble everthing make sure you have the correct Counter balancer timing by aigning the puch marks on the gears, etc. and make sure you lock tite everthing and bend over the locking feature on each of the locking washers.
[This message has been edited by Clark Mason (edited 11-28-2000).]
Posted December 11, 2000 - 03:22 AM
Posted May 08, 2001 - 08:58 AM
What did you use to hold the clutch basket while removing the screws/nuts?
[This message has been edited by Brian Meadows (edited 05-08-2001).]
Posted May 09, 2001 - 06:27 AM
Posted May 22, 2001 - 06:50 AM
Clark - did you loctite the CB gear to the shaft?
Posted May 23, 2001 - 05:05 AM
Posted May 23, 2001 - 08:06 AM
I bought a new key ($1.20) and it looks about the same as the one I removed - corners are not sharp. I'll measure the keys to see if there is any difference. I'm not quite motivated enough to make my own key... I'll try the loctite route first.
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