Drive Belt measurement

Hi kids newbie here I was diagnosing a noise at take off and yes looked at the forum the main problems seem to be glazed shoes and possibly a dry needle bearing assy. I spoke with a local honda dealer he asked me to pull the covers and look at the belt and rollers etc. I used a 12" caliper to measure the belt width several times it was very consistently 1.033" wide so I measured the original belt that the previous owner had changed by a dealer and kept for me. It measured 1.037" (I would like to know the measurement for a new belt). I see from the manual that the service limit for the belt is 1.060" so both are too narrow. Thanks Jim

Secret on belts....based on over 400,000 miles with rubber band drive scooters, over 90,000 miles with 2 new SilverWings----just change at 15,000 miles with fresh OEM belt. I hate walking, delays on trips can be expensive, dealers usually do not have belt in stock so carry new belt. SilverWing a little hard to do belt change on side of road, but can de done. In my modern scooter miles, only one broken/destroyed bel.....Helix. VA, at that time HRC took me to friend's garage. I had replacement belt, Helix easy to change belt as front pulley does not have to come off.

Belts can die of age, too.

+1 to Mr Grinsel’s counsel. But here is a pix from an earlier belt measuring post. Maybe not the best of photos, but...

Search is your friend.

Search belt.   original poster  feurwehr7   Jan. 21st 2015  page down.  The Bern has a nice home made tool to check belt.    

Noise is most likely clutch shoes.      My belt was soaked with oil at 13k and only slipped at full throttle.

Last post Feb. 02 2015 ARRRR. Might be hard to find.

I was about to comment about needing to measure the belt correctly but Tim got there first.
I wonder how many people have scrapped good belts because of this?
The best bet is to follow Honda's guidelines and change them 16K, by the time you open up to measure you might as well replace.

Mech 1 twa wrote:

The Bern has a nice home made tool to check belt.    
 

Thank you for your kind words bud

The guage was made from a perspex offcut to check the wear on the belt when I first bought my SilverWing as the previous owner had already told me he had not changed it & there was over 18,000 on the clock.
The thing most people do when measuring the belt is to take a direct measurement of the belt at it's widest point, this is wrong, you need to project the sides upwards & measure those projections across the top of the belt, as per picture in service manual (whoops) ....




.....(but you see what I mean)    

Absolute best plan is to follow the reccomendations from Honda regarding all maintenance operations bud.

For 'fullness' ...............

The guage .....



Guage in use .....



The red line is the minimum thickness as advised by Honda, as you can see that belt was actually just below spec'

There is another factor with the belts---SAFETY!!----belt breaking underway, fast lane/busy traffic---you might get run over. Belt bad way to try save money.

Awesome info using the illustration provided by both the shop manual and the Bern I measured 27.1 mm which suggested it was getting thin. with only 3,000 miles on it. So the shop changed it out this will cost me over $500 today when I pick it up. at least it is under a warranty now so they can do the next one gratis. I can't believe that any scooter can go thru 3 belts in 11,000 miles. there must be a mis aligned shaft ? the case was clean except for where the belt had rubbed on top and bottom as they are want to do with acceleration and deceleration. Thanks everyone for the valuable and informative input. I have a 2000 mile ride set up for Monday- Thursday we will see how the newest belt does.

Thin at 3000 miles, hmm makes me wonder what it was on that gauge with the new OEM belt.

Wow, I had wondered why the drive belt measurement was considered a difficult process as I had (wrongly) assumed that all I had to do was measure across the widest part of the belt...WRONG. Although if the belt has worn significantly to the point that the upper chamfer is gone, then the widest point is the correct measurement.

I might have to make up a gauge as shown by The Bern.

Firstly thanks to Admin for getting my first picture into the correct orientation

Pleased you found my post helpful Joseph

I had already ordered a new belt before I made the guage, regardless of the machine having done over the specified milage I was set to replace it for no other reason than, it's age, having spent a lot of my working life servicing cars one of the first things you do is check the the service record for the milage & date of the last timing belt change. The date is of equal importance as the materials in the belt have a finite period at which they start to breakdown & you get the subsiquent risk of breakage.
I am aware that there is no specified afe in the manual, but I'd sooner follow spend a few quid/dollars & ride it than either sit beside it awaiting recovery or push it home

To Scooter Rider from KS---who paid $500 for belt change....you got ripped off---I think belts are retail $120, good shop work would be less than an hour even if charged $100, so total of $220.

Belt life----bike over loaded riding 2 up can shorten belt life. Sidecar or trailer pulling does same.

I remember 20 years ago in Germany---Helix with sidecar eating belts every 3-5000 km. Drive line was simply not designed for the load.

Reached 50,001 apparently somewhere in mid Patagonia, there was a "ping" noise and was never heard from again
Seriously why would anyone push their luck that far for something that costs less than £100 and takes less than an hour to fit.

Probably because the belt is “outa sight, outa mind”, their scooter is running normally, they don't have the tools, FSM, mechanical expertise or workspace to do the job etc. Or they're tighter than a goblins foreskin and don't want to spend the money.

It's a bit like the posts you read about someone bragging about getting their scooter through it's annual MOT 'and I only had three Advisories'. Which translates to being a chancer who couldn't be bothered to keep his scooter in a roadworthy condition.

Right, enough of this frivolity, I'm off out on the maxi to the nearest Asian supermarket for some Japanese Kewpie Mayonnaise.

Japanese Mayo=best in world!!

No Kewpie mayonnaise today I'm afraid, first supermarket nil stock, the second hadn’t a clue what it was, or it might have been my Cumbrian accent. I can easily buy it mail order but I'd have liked to support our local shops. So I bought a load of Korean noodles instead.

More disappointment at the local Yamaha dealership too. After looking at nothing but YouTube clips of it all year, I had hoped they'd have the new Yamaha Tricity 300 in stock.  They didn't, the salesman mentioned all this years quota was in dealers elsewhere, and it'd be next year before any more would be on sale.

When I acquired my SW600 this year, new (so called) spare drive belt was included. On recent inspection, I found the installed belt was comparable with the so called new spare belt. As already mentioned above, Honda top width limit is 27mm. Does anyone have all dimensions of a new Honda OEM belt?

Installed (mm)
Top width 26.4
Bottom width 21.3
Thickness 14.4

New spare
Top width 26.4
Bottom width 21.4
Thickness 14.3

I suspect the new spare is a fake manufacturer of poor quality..?

Installed belt looks in good order after 22700km virtually no carbon fibre dust found in the drive housing and inside the movable drive assembly. It is possible the original belt was replaced earlier. However, I will change the belt at the recommended 24000km, perhaps not with my new spare..!

I don’t get all this belt measuring business, just change it every 16000 miles.

Point I was trying to make, Honda Service manual gives the top width limit 27mm. But does not specify what a new belt top dimension should be. In my particular case, I am trying to determine if my spare belt is “second hand” or just poor quality manufacture. I could image some riders may be tempted to go for non OEM belt to save money.

New belt (measured at the correct location) is 26 mm. Service limit is 25 mm.

Thanks Tim, you have answered my question. I will sleep well tonight knowing my spare belt is new.

Why did Honda choose to measure the belt at a projected point across the top face rather than the actual width of the widest point across the wearing face?

Hi Steve,

It wasn’t Honda that took the measurements, but me with my trusty Vernier gauge, accuracy approx. +/- 0.1mm. The top measurements were taken at the widest point as shown in the Honda service manual section 10.1. Unfortunately, Honda manual doesn’t give the standard “bottom” belt width, unless I’ve overlooked it.
I know I am thrashing a dead horse here, but the topic interests me for some reason, probably from my engineering design background for many years.