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Makes And Models => Zero Motorcycles Forum | 2013+ => Topic started by: TheGap on October 01, 2018, 10:16:16 PM

Title: Belt rubs against shouldered side of the rear sprocket.
Post by: TheGap on October 01, 2018, 10:16:16 PM
The belt of my bike is currently firmly rubbing the shouldered side of the rear sprocket.

I've found this helpful post (http://electricmotorcycleforum.com/boards/index.php?topic=3813) which touched the exact topic in my question and where Doctorbass gave an excellent response in his last paragraph:
If your belt is too close to the rear sproket shoulder, then you can remove the motor sproket and remove one of the spacer behind it. this is about 1.5mm thick and there is 3 of these . Then your belt should be  1.5mm far from teh rear sproket shoulder.


I have one more question though and rather than necroing a thread from 2014 I thought I'd better start a new post.
--> does this fix still apply for the Zero 2017 SR?
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: DonTom on October 01, 2018, 10:59:45 PM
The belt of my bike is currently firmly rubbing the shouldered side of the rear sprocket.
Remove nothing and try this:

Lift bike off the ground with a black widow lift. (https://www.discountramps.com/motorcycle/jacks/p/BW-1604A/)

Try loosening  the axle nut and then align the belt to the RIGHT side of the sprocket, so the right side of the belt is right on the right edge of the wheel sprocket.

Then tighten the axle bolt to spec. which will change the position of the belt. Rotate the wheel a few times and see if a credit card edge will now fit between the belt and shouldered side. When a credit card fits between the belt and the shouldered left, with the axle nut tight to spec., consider the job done. Check 360° to be sure it stays at a credit card spacing all the way around.

You want to correct that right away. I would not even want to ride the bike without that credit card spacing space as I expect it will quickly damage the belt.

Remember to hold the bike when you bring the lift down. Test ride and see if the belt still has the credit card spacing.

-Don- Reno, NV



Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: dennis-NL on October 02, 2018, 12:00:36 AM
Agree, remove nothing, just some alignment is needed.
While adjusting rear, rotate wheel a few times.
If belt is always 1mm of shoulder it's perfect.
Tighten all bolts and, to be sure, rotate again and do a small test ride.
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: togo on October 02, 2018, 12:39:43 AM
> Lift bike off the ground with a black widow lift. ...

Only use a center lift if your garage has a level floor!

(You can imagine how one learns this lesson)
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: DonTom on October 02, 2018, 03:06:31 AM
Agree, remove nothing, just some alignment is needed. While adjusting rear, rotate wheel a few times. If belt is always 1mm of shoulder it's perfect.
Tighten all bolts and, to be sure, rotate again and do a small test ride.
A credit card is  0.76 mm in thickness, so a credit card should feel a bit on the loose side between the belt and the shoulder.

Anybody know of anything more handy to use than a credit card to measure the 1mm?

-Don-  Reno, NV
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: Richard230 on October 02, 2018, 03:33:53 AM
Agree, remove nothing, just some alignment is needed. While adjusting rear, rotate wheel a few times. If belt is always 1mm of shoulder it's perfect.
Tighten all bolts and, to be sure, rotate again and do a small test ride.
A credit card is  0.76 mm in thickness, so a credit card should feel a bit on the loose side between the belt and the shoulder.

Anybody know of anything more handy to use than a credit card to measure the 1mm?

-Don-  Reno, NV

How about a 1mm thickness gauge as is sold in sets at any motorcycle or auto store to check ICE valve clearances. I have four of those gauge sets in my tool box.
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: DonTom on October 02, 2018, 04:04:01 AM
How about a 1mm thickness gauge as is sold in sets at any motorcycle or auto store to check ICE valve clearances. I have four of those gauge sets in my tool box.
I was just thinking that also, but I didn't think they went up to 1mm, I will have to check mine.

I use .006" & .008" for my ICE bikes adjustable valve clearances which is only 0.1524mm and 0.2032mm. Perhaps I can use two 0.5MM or whatever, or just stick with the credit card, which should be close enough if it's just a little on the loose side between the belt and  sprocket shoulder.

-Don-  Reno, NV

Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: Richard230 on October 02, 2018, 06:31:56 AM
How about a 1mm thickness gauge as is sold in sets at any motorcycle or auto store to check ICE valve clearances. I have four of those gauge sets in my tool box.
I was just thinking that also, but I didn't think they went up to 1mm, I will have to check mine.

I use .006" & .008" for my ICE bikes adjustable valve clearances which is only 0.1524mm and 0.2032mm. Perhaps I can use two 0.5MM or whatever, or just stick with the credit card, which should be close enough if it's just a little on the loose side between the belt and  sprocket shoulder.

-Don-  Reno, NV

If your individual thickness gauges don't go to 1mm, you can stick enough of them together to make a 1mm thickness. Assuming, of course that you have a thick set of gauges like I do.  ;)  My single thickest gauge is .89 mm and one more gauge placed next to that one will make 1mm, if you think that .9 mm is not thick enough. I believe I bought my set of gauges from Sears Roebuck many years ago.
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: TheGap on October 02, 2018, 01:30:47 PM
Thanks for all the great tips.
With the odometer at about 13000km (and thus my next scheduled maintenance) I'm going to provide the info from this thread to the shop where I've bought my bike.

Since day 1 when I got my bike I've made that remark to my original dealer. I've also asked another garage shop (where I changed my tires) to take a look at it and see if they could do something about it ... but it always remained the same and the belt always makes an annoying groaning sound.


For reference I've attached a picture of how it looks now.
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: Richard230 on October 02, 2018, 07:11:09 PM
Thanks for all the great tips.
With the odometer at about 13000km (and thus my next scheduled maintenance) I'm going to provide the info from this thread to the shop where I've bought my bike.

Since day 1 when I got my bike I've made that remark to my original dealer. I've also asked another garage shop (where I changed my tires) to take a look at it and see if they could do something about it ... but it always remained the same and the belt always makes an annoying groaning sound.


For reference I've attached a picture of how it looks now.

That spacing looks OK to me.  My feeling is that as long as you have some distance between the edge of the belt and the cog wheel flange that does not vary when the wheel is rotated, that should be good enough.  My belt tension was set right at the upper limit of tension when it came from the factory and it made noticeable groaning at low speeds when new.  However, after about 500 miles the groaning slowly disappeared.  Either that or I got  used to the noise.  ::)
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: TheGap on October 02, 2018, 08:07:02 PM
That spacing looks OK to me.  My feeling is that as long as you have some distance between the edge of the belt and the cog wheel flange that does not vary when the wheel is rotated, that should be good enough.  My belt tension was set right at the upper limit of tension when it came from the factory and it made noticeable groaning at low speeds when new.  However, after about 500 miles the groaning slowly disappeared.  Either that or I got  used to the noise.  ::)
There's an edge ... but I don't see any spacing. Certainly not when keeping in mind that the lip is slightly chamfered (see exaggerated picture I've attached).

I'm at around 13000km (~8000miles) and I still hear the groaning at any speed faster than turtle.
Whenever there's any real torque exercised on the rear sprocket I hear the belt groaning and vibrating

It's the last real annoyance I have from my zero ... the fact that, even for an electric motorcycle, it still makes too much noise

Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: BamBam on October 03, 2018, 12:52:34 AM
You don't have to be that precise.  You can just eyeball it to make sure you have a noticeable gap so that the belt never touches the sprocket throughout its rotation.  The other thing you should do is loosen up the belt so that it is at the low end of the tension range.  Refer to the Unofficial Service Manual for the tension range.  I actually keep my belt a little below the low end of the range with no adverse affects.  Both of these things will help to eliminate the groan.  Groan should pretty much disappear after about 1,500 miles.
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: SebfromBE on October 03, 2018, 01:28:53 PM
Hi all,

This is a nice thread! But I have possibly some dumb question to ask on the procedure!

Setting: Zero S 2017 - belt snapped and changed at 5000km. Now make some vibration noise (especially when low on tension) at specific speed range or when turning.

When looking at the belt alignment, it is clear fully close/touching the edge (left) of the rear sprocket. I also notice that it is more aligned towards the right edge of the front sprocket. Anyway I tried to follow the procedure here.
-Loosen rear wheel axle
-loose tension adjustment nut and adjust tension
- make sure that both sides are at the same 'mark'
- then try to 'push the belt to the right edge (which is possible)
- but then as soon as I make the wheel turn, the belt comes back in its original position (touching edge).

I tried to modify the left/right tension adjustment nuts (but not too much, since I believe they should overall be aligned). Without any visible difference in belt alignment.

Is there something stupid that I am missing?

Thanks already all for your help!

Seb
-
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: dennis-NL on October 03, 2018, 03:11:25 PM
...
I tried to modify the left/right tension adjustment nuts (but not too much, since I believe they should overall be aligned). Without any visible difference in belt alignment.
...

But it's not only adjusting nuts, also push the wheel axle against the nuts firmly, so the axle will actually move a little diagonal.
Than rotate the wheel, it really should impact belt position now!
It's even possible the belt runs of if too much adjustment, just play with it a few times in the garage too see impact of changes.

Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: SebfromBE on October 03, 2018, 03:20:47 PM
Thanks I will try tonight and let you know!

I indeed didn't try to push specifically the axle to force it in place...
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: Richard230 on October 03, 2018, 07:49:39 PM
Plus, just about all motorcycle rear wheel adjustments (chain or belt driven) move a little when you fully tighten the axle bolt after apparently getting the adjustment just right. Sometimes you just have to loosen the bolt and adjust the wheel alignment again to get it aligned correctly. Also you can't always depend upon the alignment markings on the swing arm. Those marks are typically not 100% accurate. You just need to align the rear wheel so that the belt runs near the center of the cogwheel without moving as it is rotated. Sometimes that takes a little guessing and trial and error with the alignment screws.
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: SebfromBE on October 04, 2018, 01:35:20 PM
Thanks all for your help!

I did play a bit more (and took more time  :P) and finally found what you described.

Looks much better now, but indeed the 2 markers are not fully aligned, which still sound a bit scary to me (you get an aligned belt but potentially a misaligned wheel).

But then OK, these bikes don't reach super high speed :-)

Cheers,

Seb
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: TheGap on October 05, 2018, 07:09:04 PM
Like previously mentioned, when taking the chamfered side into account I don’t see any clearance between the belt and the shouldered side of the rear sprocket (see “Belt inside view.jpg”).

Even some wear traces on the belt show this when you compare the pictures with the two sides of the belt (see “Belt side views.jpg”, bottom one is the shouldered side).

So all in all I do think I’ll need to get more clearance.
What do you guys think?
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: Richard230 on October 05, 2018, 07:29:30 PM
I agree. The alignment of your drive belt could use a little tweak away from the cog wheel flange.  ;)
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: NEW2elec on October 05, 2018, 08:03:40 PM
I read all this and tweeked mine and got the little gap back from my last wheel removal, so thanks guys for that.
TheGap two things to check as well are the sprocket "true" and wheel "true".
With the bike jacked up and off of course, hold a pencil or other straight object perpendicular to the swing arm so that it just touches the edge of the sprocket.  Now spin the wheel while holding the pencil steady against the swing arm and see if it rubs in some areas and not others.
Mine had a tiny wobble but I got my belt riding correctly.  A warped sprocket will never align properly.
Do the same thing on the right side but hold the pencil to the wheel rim and check the same thing to see if the wheel is out of true.

If it is all true still than you can adjust the belt tension. Loosen the axle nut, and the tension bolt's front lock nut.  Mine took a 13mm wrench.
It is amazing how very little you have to turn the tension bolt to get quite a change in belt tension.
For your problem you will want your right side (brake side) to be slightly and I mean slightly forward.
The belt rubbing the sprocket shoulder isn't good but the belt sliding off to the inside of the wheel is very bad.
Be sure to spin the wheel a few times to see where the belt will ride on the sprocket.

When you tighten the locking nut back down its best to have two 13mm wrenches to hold the tension bolt still while turning the locking nut otherwise you'll have to watch and see if it moves and readjust it if it does.

Like Richard said when you torque the axle nut it may move a little so spin the wheel a few more times to see if it changes too much before lowering it.
Short safe test ride to check it under load and with any luck you got it.
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: TheGap on October 05, 2018, 08:15:47 PM
I read all this and tweeked mine and got the little gap back from my last wheel removal, so thanks guys for that.
TheGap two things to check as well are the sprocket "true" and wheel "true".
With the bike jacked up and off of course, hold a pencil or other straight object perpendicular to the swing arm so that it just touches the edge of the sprocket.  Now spin the wheel while holding the pencil steady against the swing arm and see if it rubs in some areas and not others.
Mine had a tiny wobble but I got my belt riding correctly.  A warped sprocket will never align properly.
Do the same thing on the right side but hold the pencil to the wheel rim and check the same thing to see if the wheel is out of true.

If it is all true still than you can adjust the belt tension. Loosen the axle nut, and the tension bolt"s front lock nut.  Mine took a 13mm wrench.
It is amazing how very little you have to turn the tension bolt to get quite a change in belt tension.
For your problem you will want your right side (brake side) to be slightly and I mean slightly forward.
The belt rubbing the sprocket shoulder isn't good but the belt sliding off to the inside of the wheel is very bad.
Be sure to spin the wheel a few times to see where the belt will ride on the sprocket.

When you tighten the locking nut back down its best to have two 13mm wrenches to hold the tension bolt still while turning the locking nut otherwise you'll have to watch and see if it moves and readjust it if it does.

Like Richard said when you torque the axle nut it may move a little so spin the wheel a few more times to see if it changes too much before lowering it.
Sort safe test ride to check it under load and with any luck you got it.
Thanks for the info but it will probably be more useful to future readers than me (... which means it's still VERY useful) because I don't do any work on my bike myself and let the shop take care of it.

I now have the confirmation I need that this alignment is far from optimal and needs to be fixed.
And if need be I can point the shop to this thread if they have any doubts about alignment or procedure.
... waves to EcoMobiel shop  8)
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: BamBam on October 05, 2018, 08:36:10 PM
Here are a couple of photos of my sprocket with the belt properly aligned.  As you can see, there is some sprocket visible on the shoulder side, but there is more visible on the wheel side.  I would say the gap at the shoulder is between 1.0 - 1.5 mm.  Probably closer to 1.5 mm.
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: ESokoloff on October 06, 2018, 08:33:50 AM
Plus, just about all motorcycle rear wheel adjustments (chain or belt driven) move a little when you fully tighten the axle bolt after apparently getting the adjustment just right. Sometimes you just have to loosen the bolt and adjust the wheel alignment again to get it aligned correctly. Also you can't always depend upon the alignment markings on the swing arm. Those marks are typically not 100% accurate. You just need to align the rear wheel so that the belt runs near the center of the cogwheel without moving as it is rotated. Sometimes that takes a little guessing and trial and error with the alignment screws.

Here's my notes on the subject........ (NOTE: This is on/for my 16 DSR).

20/30kg tension via a Krikit  https://www.google.com/search?q=krikit&rlz=1C9BKJA_enUS630US630&oq=krikit&aqs=chrome..69i57j0l3.2960j0j9&hl=en-US&sourceid=chrome-mobile&ie=UTF-8

Jacking left screw(bolt) out (adding tension) moves the belt to the right.
Best to get the belt in the correct position (left/right) then adjust tension.
NOTE: Position belt with a right side biases as it will shift to the left when the axle bolt is tightened.     
Must use rolling head prybar to pry the right side towards its jack-screw (or just Smack the tire/rim in the desired direction) 
Spin the wheel several times after an adjustment to allow the belt to settle down & find its new position.
NOTE: 1/6 turn of Left jack screw appears to cause a 10KG difference to tension.
Use 1-1/16" socket to tension axle nut to 102NM (75#/') when compleat (I don't have the correct Metric socket but found that 1-1/16" is close enough to work).

P.S.  Recomend first removing each Jack bolt & grinding down the raised print on the heads to prevent digging into the soft aluminum of the swing arm.
Also apply some anti-seize to the threads before re-installing. 
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: PVNRG on May 18, 2020, 08:05:32 AM
The belt alignment was excellent until a couple of weeks ago. No adjustment were made. All of a sudden there was loud squeaking noise that I noticed at low speed when pushing the bike forward or backward. Kept riding with no issues but put bike on stand today to check things out. The belt is no longer in alignment between the sprockets. It is so far out of alignment that the belt is twisted at the rear sprocket. Nothing had been changed with the tension adjustment bolts. It now appears that the sprockets are not lined up and it is a big distance. Looks like maybe an 1/8 inch offset or so. I can't figure out what happened. The rear sprocket is not damaged and was tested true with a flat bar held on the swingarm to check distance to the outside edge of the sprocket. My only guess at this point is that somehow the front sprocket moved away from the motor by 1/8 inch or so. This does not seem possible though. The first time the belt broke the motor side tack welded ring fell off so I had to remove the sprocket and weld it back on. It was VERY difficult to remove it and was also very tight going back on. The set screw was torqued onto the key and the the coaxial bolt lock tight and tightened onto the shaft when it was reinstalled. I don't think it could come undone on its own. Does anyone have any suggestions? Thanks!! Here (attached?) is a photo:
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: TEV on May 18, 2020, 09:22:09 AM
The belt alignment was excellent until a couple of weeks ago. No adjustment were made. All of a sudden there was loud squeaking noise that I noticed at low speed when pushing the bike forward or backward. Kept riding with no issues but put bike on stand today to check things out. The belt is no longer in alignment between the sprockets. It is so far out of alignment that the belt is twisted at the rear sprocket. Nothing had been changed with the tension adjustment bolts. It now appears that the sprockets are not lined up and it is a big distance. Looks like maybe an 1/8 inch offset or so. I can't figure out what happened. The rear sprocket is not damaged and was tested true with a flat bar held on the swingarm to check distance to the outside edge of the sprocket. My only guess at this point is that somehow the front sprocket moved away from the motor by 1/8 inch or so. This does not seem possible though. The first time the belt broke the motor side tack welded ring fell off so I had to remove the sprocket and weld it back on. It was VERY difficult to remove it and was also very tight going back on. The set screw was torqued onto the key and the the coaxial bolt lock tight and tightened onto the shaft when it was reinstalled. I don't think it could come undone on its own. Does anyone have any suggestions? Thanks!! Here (attached?) is a photo:

Looking at your mileage, maybe the swing arm has some bushings that got some play ? You should check the motor  sprocket too, just in case.

EDIT: It seems that it has bearings: 
"Part number 20-06138, BEARING 6204
Bearing used as swing arm bearing in some models and
as the wheel bearing (qty of 5; 2 in front and three in rear wheel)
in 2015 and later models.
 NOTE: Manufacturer part number is 6204-2RS"


Good luck!
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: Richard230 on May 18, 2020, 08:15:41 PM
You might also want to check the condition of the rear wheel bearings. Perhaps they have failed. You would have to do that anyway in order to check the swing arm bearings and motor sprocket.
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: ESokoloff on May 18, 2020, 10:35:59 PM
The belt alignment was excellent until a couple of weeks ago. No adjustment were made. All of a sudden there was loud squeaking noise that I noticed at low speed when pushing the bike forward or backward. Kept riding with no issues but put bike on stand today to check things out. The belt is no longer in alignment between the sprockets. It is so far out of alignment that the belt is twisted at the rear sprocket. Nothing had been changed with the tension adjustment bolts. It now appears that the sprockets are not lined up and it is a big distance. Looks like maybe an 1/8 inch offset or so. I can't figure out what happened. The rear sprocket is not damaged and was tested true with a flat bar held on the swingarm to check distance to the outside edge of the sprocket. My only guess at this point is that somehow the front sprocket moved away from the motor by 1/8 inch or so. This does not seem possible though. The first time the belt broke the motor side tack welded ring fell off so I had to remove the sprocket and weld it back on. It was VERY difficult to remove it and was also very tight going back on. The set screw was torqued onto the key and the the coaxial bolt lock tight and tightened onto the shaft when it was reinstalled. I don't think it could come undone on its own. Does anyone have any suggestions? Thanks!! Here (attached?) is a photo:

From the image it’s hard (impossible) to determine if the rear sheave pivoted CW or the motor sheave moved outboard (from motor).
If the former, belt tension would decrease.
If latter, belt tension would slightly increase.

The only changes made were the removal & re-installation of the motor sheave. 
That’s were I would concentrate my efforts on. 

Put the bike on a stand or jack so rear wheel is off the ground.
To check sheave alignment (drift), take a piece of string 3x the distance between the sheaves & wrap the center of the string once around the belt.
Rotate the rear wheel so the belt carries the string around the motor sheave edges (but is not making contact with motor shaft.
Now take each end of string and use like two individual straight edges to determine how much (if any) drift there is between the two sheaves. 

Please let us know the outcome for our knowledge.
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: PVNRG on May 25, 2020, 07:29:34 AM
Thank you for the advise!!

I had new tires installed at the motorcycle shop on Friday and I'm loving them so far. Scorpion Trail II. The mechanic checked the wheel bearings as said they were in good condition.

I'm having trouble understanding how to setup the string to check alignment between the sprockets.

Probably going to put the bike up on the hydraulic table tomorrow and take off the swingarm to check things out. Right now I'm hoping that the motor sprocket somehow came loose a little bit and shifted left.
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: PVNRG on July 14, 2020, 08:06:41 AM
Belt teeth got torn up today so I finally have the swingarm unbolted and held out of the way. Turns out that the swingarm bearings are "crunchy". I'm hoping that is why there is sprocket to sprocket misalignment. Tried to loosen front sprocket bolt with 1/2 inch impact but it did not budge. I don't think that the front sprocket moved to cause the misalignment. The swingarm bearing are crunchy but they seem to be solid, not loose at all. This is still a mystery to me. Anyway, I think I should replace the bearings regardless. Anyone know what bearings to use? The unofficial manual was not very clear on which ones to use.
Title: Re: Belt rubs against shouldered side of the rear sprocket.
Post by: togo on December 12, 2020, 12:23:25 AM
PVNRG> ... The swingarm bearing are crunchy but they seem to be solid, not loose at all. This is still a mystery to me. Anyway, I think I should replace the bearings regardless. Anyone know what bearings to use? The unofficial manual was not very clear on which ones to use.

Were you able to get them out and match them up?  The unofficial manual can be corrected...