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Hi guys it’s me again
Could you please tell me the best way of getting the drive sprocket off ??

Insert one of the grub screws into the upper most hole, screwing it in will push the sprocket off. The instructions for this are in the manual somewhere. Just make sure the 2 locking screws are removed before you try otherwise it will be a lot of fun. I see your are already out.

Yes Adrian told me this but it’s proving to be very difficult, I was thinking about some sort of puller

Hi John,

I use a gear puller, if the screw doesn´t do the job.

Cheers

Peter

Hi Peter do you put the hooks behind the drive sprocket??

Hi John, Yes I do. I place the three hooks behind the sprocket and place the tip of the middle pin into the hole in the axle. Then you can pull the whole assembly off by screwing the middle pin clockwise. Cheers Peter

The problem with taper locks is if you pull them they tighten more so a puller is a last option IMO.

Try doing it the proper way first, but sometimes the taper lock bites into the alloy hub which is why we get problems, I have removed hundreds of industrial Taperlock's with no issues but they are all used on cast steel pulleys not alloy. The alloy ones are harder to remove IMO.

Hi John,
Yes, its a common problem. As Paul says, in theory using a puller can tighten things up. For the taper removal to work as intended and the separation forces to be applied properly, the single grub screw (at twelve o'clock in your photos) needs to bite into the thread on the side of the taper and slide freely against the smooth alloy side of the sprocket. The problem I find is that as you wind the grub screw in, it gets pushed sideways away from the taper lock and cuts its own thread in the soft alloy of the sprocket - so when it gets to the bottom of the hole it simply binds up against the new thread in the alloy rather than applying a lifting force to the taper.
If this has happened to you, possible options are:
- use a small file to try an smooth away the threads in the alloy,
- apply grease to the grub screw so that it is more inclined to slip on the alloy
- try and get some thin steel shim between the grub screw and the alloy to stop it binding.
- With all the grub screws out, put a spacer with an internal hole diameter greater than that of the taper lock ( eg a large socket) over the taper lock so that it only acts on the sprocket and give it a good sharp blow with a hammer - unfortunately you can only do that once or twice before the whole assembly slides down output shaft and bottoms out on the gear casing - but at least it gets things moving.
Good luck !

David

Thanks David
I can’t believe how hard this is to remove , hopefully Armortek will come up with something different im the future

Johndavey wrote: ↑

Wed Apr 16, 2025 3:57 pm

Hi Peter do you put the hooks behind the drive sprocket??

Here is a pic: Using the gear puller, I never had any problems pulling the assembly off.

John, the key in your taper lock is in sideways - this would not have helped in the fitment and probably makes removal more difficult.

As peter suggested, a gear puller may help. Screw in the middle screw, apply a bit of pressure with the gear puller and tap the sprocket with a soft mallet. You can also try applying heat to the taper lock before increasing the pressure on the gear puller.

Morning John
This is a very touchy subject which has more different approaches than you would imagine and my opinion is just another one to add to the list. Yes, I have fitted one or 2 of these over the years and had some “fun” with them, they are an extremely effective means of locking pulleys to shafts but they can also be tricky especially after 10-15 years in a nasty environment.

My first experience with the AT sprocket (many years ago) was with a 2005 Tiger 1 I acquired that had done a lot of work so required a complete over haul, and when I got to the drive sprocket I had quite a surprise as the original hubs had no bottom to the 3rd hole. The 3rd hole the one used for releasing the lock was drilled completely through so the grub screw had nothing to push against, which made things interesting. I am a very strong believer that you should never use a puller on a TIGHT tapper lock, you may get away with it once or twice but the nature of the locking system is that it will get tighter. To fix my problem I make a small tool to help separate the taper bush from the hub, which got me out of trouble and has come in very handy as I have had quite a few occasions that required it, and I have found that it is the best way to get a tapper bush out that has broken in half, broken bushes can be fun.
I also totally agree with Dave’s comment on the 3rd hole issue, what I have found is that sometimes there is a slight variation in the size of the tapper in the hub and the location of the 3rd hole, the Sherman E8 was very tricky as the tapper was very deep in the hub the 3rd hole too close to the centre, or slightly too small. So as Dave said if the grub screw does cut into the hub or leave any marks then you will have to grind/file the hole slightly large, I use a small bit in the Dremel, don’t go crazy on it, a little bit at a time checking the fit in between until the grub screw is a nice fit, a little loose won’t hurt but not too loose as the screw will walk out of the thread in the bush. Yes, you have the key in the wrong way but standard keys should be square and once you release the taper lock the bush can open slightly which should allow it all to slide off. As Paul and Dave mentioned, I strongly recommend against using a puller BUT, on the occasion that the bush has locked onto the shaft (usually rusted on after years of service) or if the key is jamming the bush on the shaft a puller can be used. Once the taper bush and the hub have been UNLOCKED, and the hub and bush should move freely on each other then you can use a puller as long as the 3rd screw keeps the hub and bush separated so that they do not lock again. If a puller is required, then set the 3rd screw so that it just holds the hub and bush apart if the screw is in too far in you may break the bush in half if it is too shallow the hub and bush may lock again. When I say the 3rd screw I mean the screw used in the 3rd hole.

I hope that helps?

Good luck
Liam

Thank you Liam what a nightmare

So eventually I managed to pull the drive sprockets off with no real effort , would like to thank all you guys who helped me and gave me some great advice much appreciated
John

Johndavey wrote: ↑

Thu Apr 17, 2025 4:11 pm

So eventually I managed to pull the drive sprockets off with no real effort , would like to thank all you guys who helped me and gave me some great advice much appreciated
John

How, im bound to get it wrong so need to know how to remove it.