Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 Belt noise

Looks like the Spax adjustables.

Yes they are the Spax adjustables.

I removed my trailer mudguard for clarity, set the engine at 2500rpm with the aid of a long brush which can be seen in the video. It didn't take long before the BB was quite hot at the input end although remained reasonably quiet. A stethoscope on the casing suggested it was no more noisier than the gearbox.

I had just re-filled the BB with 450ml of Millers EP140.

My next modification is to fabricate an NACA duct into the removable section of the floor pan so cold air from under the car will be directed up and over the nose of the BB.

Photos to follow in due course.

With all due respect, I am not sure how meaningful the test with virtually no load on the BB (i.e. rear wheel in the air) will be.

I notice that my BB is much noisier under load (i.e when the engine is pulling the car along) than when I ease my foot off the throttle and the BB is just rolling.

I also assume that noise is related to friction, which in turn is related to the heating effect of the internals. Hence again, it may get considerably hotter when under under normal load.

If I can ever figure out how to post pictures to this site, it will happen!

I just received the reworked sprocket from Super Max. They machined off the teeth as well as removed the outside bolt-on flange. The new neoprene teeth now has a built-in inside flange. The outside flange has no mount points left so it will revert to being flangeless like the first sprocket I had. The whole works appears to be beautifully bonded to the original aluminum as well as having bolts set in the valleys every three inches or so. Very nice.

Below is the blurb that was sent with it:

DO NOT “OVERTENSION” BELT

We at Super Max strive to give you excellent belt drive products. We perform many pulley rebuilds. Each and every Over-Lay is hand cast and hand machined to exacting specifications to fit the need of each and every customer’s personal requirements. We have approximately 6 painstaking days in each Over-Lay to insure that you, the customer, are getting the very best possible service and parts.. For “YOUR” motorcycle.
The average rear belt is “SEVERELY” Over-Tensioned. This extreme tension can cause a myriad of problems with belts, pulleys, bearings and seals as well as premature belt failure. It is best if you have some play in the belt. On swing arm bikes 3/4” with two people up is a pretty good starting spot. If the belt does not ‘Ratchet” (Slip a cog) it’s not too loose. Over tensioned and misalignment must be addressed.
Give your new Super Max a break and utilize a looser belt tension than is common on many bikes. The over tightening of belts can cause premature failures.
Your Super Max pulley will last you for years if properly cared for.

And noisy!

Look forward to hearing how you get on with it Michael , I'm hoping you've found the solution !

Michael,

Pictures added as promised. I'll be interested to see how you get on with this. Are you able to give us any idea of cost?

Michael great pics...looks true quality and a great fix.

On my M3W the only fix I did was to apply a grease as previously posted.
But as said only a 500/600 mile short term fix.

I do admire the engineering ingenuity of TMers.....fantastic!

Total cost was $535 + $40 for shipping UPS in the states.

For those who care, it can be made with any color. I opted for the default black as one can hardly see the wheel! Sprocket, what sprocket?

Thank you John for your kind help with the pix!

Just one quick note on "loose" belts.

When the cogs of the belt are fully engaged into the sprocket, as in running on the "tight" side, you get just a straight pull on the belt and it does what it's supposed to do.

But when a belt is allowed to run looser, the cogs can ride up the sprocket flights and as they come up and the round of the belt cog gets close to the top of the sprocket tooth, it works like a lever and can actually put a LOT more stretch pressure on the belt. This has been proven over the years on Harleys with broken belts.

As all here know, the correct tension of a belt is very subjective and finding the sweet spot is not too easy.

A rule of thumb on the Harleys is that if you can grab the belt in the middle bottom and with your fingers twist it 90 degrees, its about the right tension. If the belt is too loose you can twist it past 90 and of course if it's too tight, you cannot get 90 out of it.

I would just tread lightly about running belts "loose" versus a bit more on the tighter side.

Just my opinion, but wanted to throw it out there for more information.

When the overlay sprocket information hit my computer some time back, I did a quick review of the site and it looked promising and I too will be very interested in knowing how well it works.

But after riding belt driven Harleys now for some time, I can say that belt wear, pulley wear and belt noise never comes up as a problem or even an annoyance in person or on any of the forums I participate in. Just say'n!