Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 Supermax

You're right, it would have damaged the belt if it had been run like that - but in the photo I had just partially unscrewed it prior to re-gluing!

When I tapped the pulley I used a taper tap so the grub screws would tighten up and not pass completely through the pulley. Up to press all appears to be good.

Excellent information for those using Supermax sprockets. Very little is ever perfect but if you know what to look for then you can greatly reduce the chances of it failing at the most inconvenient time.

Last week, after 16185 miles, my Supermax pulley finally gave up the ghost on the Antwerp ring road. Given the choice, I would have preferred for it to have happened closer to home but hey-ho.



With the benefit of hindsight, I got it completely wrong in my post (dated 3rd June) in this thread. It's now clear to see that what I thought were shortened grub screws were in fact full length ones that had sheered off. Therefore, at that time there were probably only 3 full length screws remaining so a disastrous outcome was all but inevitable.




Looking at what’s left of the grub screws, they appear to be quite soft and malleable. Stainless steel maybe? Why on earth don’t Supermax use high tensile grub screws that would resist sheering?



If I had my time again, I would double-up on the screws, using high tensile ones this time. I'm sure that would have saved the holiday, prevented a lot of stress for me and Mrs Bunny (not to mention saving me from parting with a substantial amount of wonga).

Massive shout out to Chas & Steve at M3W Services (France) who pulled out all the stops to get a replacement pulley sent out to me as soon as humanly possible. Thanks guys!

Hi Bunny, don't know if you remember but that happened to me up in the Yorkshire Dales a few years ago.

I managed a successful repair with 2 pack epoxy glue and new grub screws. I drilled all the way through the pulley and used a taper tap so the new parallel grub screws would not just pass through but would tighten up. These were loctited in.

Fortunately I could get recovery back home to do the repair overnight and then continue the trip the day after. Not that easy when you're in Antwerp though.

Yes, I do remember your super-human effort & I'm only sorry that I wasn't able to do similar due to the lack of facilities and impenetrable language barrier. There's a lot to be said for a home workshop! Do you think your pulley had done around the same mileage as mine (16k) before it failed? With the benefit of hindsight, I reckon the screws began sheering off one by one fairly soon after I fitted it. As eluded to, the pulley has now been replaced with a new one, which is itself going to be replaced with a Fabian lightweight steel one before I venture out to the Isle of Man later this month. Therefore, there will soon be one very low mileage (180 miles) Supermax pulley on the market at a knock-down price if anyone's interested!

Rejoining this conversation after three years. My Morgan steel pulley replacement acquired after the SuperMax failure is still going strong and as quiet as ever. No regrets.

I did notice when it was swapped out that the loose and missing screws did damage the main belt right in the middle. After looking at it, both my dealer and I decided to just use the belt as its structural integrity was hardly effected. It is still on and doing well.

I have never noticed the weight difference between the steel and alloy sprockets. I have also lost weight (about 15 lbs) but acquired wife so all things evened out.

That is all...

Hi Andy

Yes it was around 16k miles, and I also suspected the grub screws came out 1 at a time until the remaining ones could no longer cope with the torque, mine you I did have a passenger at the time which probably didn't do it any favours.