Commando Isolastics

The front mount is easy as the whole unit can be removed and rebuilt on the bench. I would recommend fitting standard Isolastic bushes and fitting the Mick Hemmings adjustable end stop. The rear Iso needs the cradle taking off to replace the rubbers, that's why they are left unserviced so often. again a Mick hemmings item fitted here is the way ahead. The Vernier fittings of the Mk3 require shortening of the front iso mounting tube. The rear iso and cradle removal is almost a complete bike dismantle job.

If the PO has done a rebuild he should have replaced the rubbers. If the rubbers are good all round your best bet is simply the Hemmings conversion at about £35 for each mount.

I upgraded my 72 Commando isolastics and engine cradle just before heading for the Brixham Rally. It is a fairly straight forward task but you do have to dismantle all the big chunks and associated peripheral parts.

So the engine, gearbox and primary drive have to be parted. The rear wheel, oil tank and its plumbing, along with the headsteady, carbs, coils and Z plates will all need temporary new homes.

Watch out for any shims on the crankshaft and also behind the clutch. There is/are spacers behind the inner primary chaincase to space it level with the engine and gearbox faces. The gearbox also has a single spacer on one of its mountings. Don't loose it or forget where it goes. To get the gearbox out I also had to remove the g/box adjuster which is bolted to the plates.

The swinging arm can be left attached to the gearbox plates but of course the rear suspension units also need unbolting. Which in turn lets the chainguard flap about.

My advice would be to ask for assistance from someone who has done such an interesting task previously. It took me 8 hours to dismantle, label and box all of my Commando bits but 28 hours to reassemble them on my own. Some jobs like dismantling the primary drive need special tools and re-assembling most of the big bits and torquing up the nuts would be easier with three hands. Re-attaching the mainstand on my Commando was hugely time consuming as none of the orignal bolts fitted the replacement cradle. I also had to work out where to drill holes in the cradle to mount the oil filter. This has to be in the correct position otherwise the swinging arm or stand will start thumping it.

Previously phil_hannam wrote:

I upgraded my 72 Commando isolastics and engine cradle just before heading for the Brixham Rally. It is a fairly straight forward task but you do have to dismantle all the big chunks and associated peripheral parts.

So the engine, gearbox and primary drive have to be parted. The rear wheel, oil tank and its plumbing, along with the headsteady, carbs, coils and Z plates will all need temporary new homes.

Watch out for any shims on the crankshaft and also behind the clutch. There is/are spacers behind the inner primary chaincase to space it level with the engine and gearbox faces. The gearbox also has a single spacer on one of its mountings. Don't loose it or forget where it goes. To get the gearbox out I also had to remove the g/box adjuster which is bolted to the plates.

The swinging arm can be left attached to the gearbox plates but of course the rear suspension units also need unbolting. Which in turn lets the chainguard flap about.

My advice would be to ask for assistance from someone who has done such an interesting task previously. It took me 8 hours to dismantle, label and box all of my Commando bits but 28 hours to reassemble them on my own. Some jobs like dismantling the primary drive need special tools and re-assembling most of the big bits and torquing up the nuts would be easier with three hands. Re-attaching the mainstand on my Commando was hugely time consuming as none of the orignal bolts fitted the replacement cradle. I also had to work out where to drill holes in the cradle to mount the oil filter. This has to be in the correct position otherwise the swinging arm or stand will start thumping it.

..........but as noted abovefitting the Mick Hemming adjusters is a simple job, provided you are happy that the rubbers are OK. I have seen mention that the MH units can self- tighten in use, this has not happened to mine but I fitted some extra grub screws just in case. I think that the MH adjusters probably are not as user friendly as the Mk111 units, but they are a big, worthwhile and easyimprovement on the pre-Mk111 system and I am very pleased with them.