First questions...

Hi

1. See my bike still on the first page here under 'Bought a bike' title. Les Emery reckons I need to swop the disc to the other side to avoid death? Wasn't the MK3 on the LH side?
2. My bike has a Boyer Power box fitted and so far I can't see anything else except the boyer trigger unit inside the points cover. Shouldn't there be a boyer ignition box or does the power box generate the spark as well? It may be hiding under the tank but it doesn'tl ook to be there?
3. The battery strap is missing. There is a pivoting loop adjacent to the back of the oil tank and a lip on the very left of the bottom of the battery tray where it looks a rubber strap will fit. Is this the only battery retention on a mk2a and will it stretch over the 14AH sealed battery that has been fitted? Is that size battery the recommended 'norm' or too big?
4. The bike smokes out of the RH pot on start up but then seems to disappear. Valve guide seal or oil pooling?
5. Finally I have no idea if the layshaft brg has been done. Gearbox out job or can you generally tell when they are starting to fail?

Feel free to post normal forum type abuse for inadequate searching

Thanks

FastFred said:

Hi

Feel free to post normal forum type abuse for inadequate searching

Thanks

Click to expand...

This.



:mrgreen:

FastFred said:

1. See my bike still on the first page here under 'Bought a bike' title. Les Emery reckons I need to swop the disc to the other side to avoid death? Wasn't the MK3 on the LH side?

Click to expand...

But what were his reasons for saying that?

I'm guessing Mr Emery may have the opinion that with the uprated brake caliper assembly in the "leading" position on the left side, the caliper mounting lugs on the slider could fail because they are under tension rather than compression during braking, although I'm certain that type of uprated brake assembly has been fitted to many MkIII models which do normally have their front brake on the left, and so far, no-one has ever reported a failure that I'm aware of?

2. My bike has a Boyer Power box fitted and so far I can't see anything else except the boyer trigger unit inside the points cover. Shouldn't there be a boyer ignition box or does the power box generate the spark as well? It may be hiding under the tank but it doesn'tl ook to be there?

Click to expand...

People have been known to get the names muddled, and may mistakenly refer to a Boyer ignition box as a Power box?

A Boyer Bransden "Power Box" is a voltage control unit, which replaces the original separate Lucas Zener diode regulator and rectifier units, it is not an electronic ignition unit, of which Boyer makes four types that are in common use on Commandos at present, the black box analogue "Micro MkIII and "Micro MkIV", the red box "Micro Digital" and blue box "Micro Power".

3. The battery strap is missing. There is a pivoting loop adjacent to the back of the oil tank and a lip on the very left of the bottom of the battery tray where it looks a rubber strap will fit. Is this the only battery retention on a mk2a and will it stretch over the 14AH sealed battery that has been fitted? Is that size battery the recommended 'norm' or too big?

Click to expand...

The original strap and buckle will easily hold a battery of that size, although you don't actually need a 14AH battery.

5. Finally I have no idea if the layshaft brg has been done. Gearbox out job or can you generally tell when they are starting to fail?

Click to expand...

DO NOT LEAVE THIS TO CHANCE!

As the original layshaft ball bearings have been known to fail with little or no warning,-which can often result in expensive gearbox damage-but more importantly, if and when it does happen, the rear wheel usually locks solid regardless of what speed the bike is travelling at, which may result in a serious accident, and pulling the clutch will have no effect! Did Mr Emery tell you that?

The only advance warning of impending layshaft failure you are likely to get is of a kickstart lever that apparently moves downwards of its own accord when the bike is accellerating hard.Therefore I would recommend you check/change the layshaft bearing as soon as it is reasonably convenient for you to do so, and you do not have to remove the gearbox to change the bearing. If you find a roller bearing or phenolic cage ball bearing in there, then no further action needs to be taken, which may seem like a lot of trouble to go to, but at least you will know what's in there.

L.A.B. said:

I'm guessing Mr Emery may have the opinion that with the uprated brake caliper assembly in the "leading" position on the left side, the caliper mounting lugs on the slider could fail because they are under tension rather than compression during braking, although I'm certain that type of uprated brake assembly has been fitted to many MkIII models which do normally have their front brake on the left, and so far, no-one has ever reported a failure that I'm aware of?

Click to expand...

Possibly an early style front end, (mounted wrong way 'round), can have the bearing retainer unscrew itself?

grandpaul said:

L.A.B. said:

I'm guessing Mr Emery may have the opinion that with the uprated brake caliper assembly in the "leading" position on the left side, the caliper mounting lugs on the slider could fail because they are under tension rather than compression during braking, although I'm certain that type of uprated brake assembly has been fitted to many MkIII models which do normally have their front brake on the left, and so far, no-one has ever reported a failure that I'm aware of?

Click to expand...

Possibly an early style front end, (mounted wrong way 'round), can have the bearing retainer unscrew itself?

Click to expand...

That was debated here before and someone said that even if it could unscrew, where would it go? Won't the dust cover/spacer hold it in place?

Thanks. Yes it definitely says power box on it and I have had the ignition units before so I know what they look like. I'll take the tank off to see if it's hiding there.

grandpaul said:

Possibly an early style front end, (mounted wrong way 'round), can have the bearing retainer unscrew itself?

Click to expand...

Yes, the bearing retainer issue has been discussed here a number of times, although I think the general consensus is that the retainer couldn't actually unscrew itself if the wheel/brake was reversed.

FastFred said:

Thanks. Yes it definitely says power box on it and I have had the ignition units before so I know what they look like. I'll take the tank off to see if it's hiding there.

Click to expand...

That's where you'll find them 99% of the time...

The two I have had before had it mounted behind the upper transverse frame plate behind the oil tank...

Boyers Commando specific instructions recommend placing it above the coils under the tank so it is most likely there.