What Did You Do With Your Commando Today?

Bonz, it is possible that when those seals were fitted that the grooves were not properly cleaned out. They can get hard calcium like deposits in them which need scraping out meticulously, otherwise the new seals stand proud and can cause the pistons not to retract properly.

It could be mate, though on a quick glance, the grooves look pretty clean, but I'll have a deep dive over the weekend, prior to (hopefully) refitting and bleeding.

I was just reading the workshop manual actually as the AN tech database differs in it's approach to inserting the outer piston & seal. The manual says, outer seal in first, followed by the piston. AN says...

'The front seal will be butchered by the sharp open lip of the caliper piston. Hence always put the pistons into the seals with the closed end first, which means the outer piston must be put into the body first, then the seal, and then be levered into the seal from the middle of the caliper.'


Regarding the seals standing proud, the Norton workshop manual says..

'It will be noted that the diameter of the seal is larger than that of the seal groove, in order to provide an interference fit. In addition, the seal groove and seal are different in section so that when bedded, the seal feels proud to the touch at the edge furthest from the bore. This is normal.'
 
It could be mate, though on a quick glance, the grooves look pretty clean, but I'll have a deep dive over the weekend, prior to (hopefully) refitting and bleeding.

I was just reading the workshop manual actually as the AN tech database differs in it's approach to inserting the outer piston & seal. The manual says, outer seal in first, followed by the piston. AN says...

'The front seal will be butchered by the sharp open lip of the caliper piston. Hence always put the pistons into the seals with the closed end first, which means the outer piston must be put into the body first, then the seal, and then be levered into the seal from the middle of the caliper.'


Regarding the seals standing proud, the Norton workshop manual says..

'It will be noted that the diameter of the seal is larger than that of the seal groove, in order to provide an interference fit. In addition, the seal groove and seal are different in section so that when bedded, the seal feels proud to the touch at the edge furthest from the bore. This is normal.'
Weird to see that in an AN doc. Must have been written long ago. I've replaced many pistons with the AN stainless ones and there is no sharp edge! Maybe if they were worn and you were just changing the seals it would be an issue. Some of the originals I seen are sharp.

IMHO, with new AN stainless pistons there is no issue.
 
It could be mate, though on a quick glance, the grooves look pretty clean, but I'll have a deep dive over the weekend, prior to (hopefully) refitting and bleeding.

I was just reading the workshop manual actually as the AN tech database differs in it's approach to inserting the outer piston & seal. The manual says, outer seal in first, followed by the piston. AN says...

'The front seal will be butchered by the sharp open lip of the caliper piston. Hence always put the pistons into the seals with the closed end first, which means the outer piston must be put into the body first, then the seal, and then be levered into the seal from the middle of the caliper.'


Regarding the seals standing proud, the Norton workshop manual says..

'It will be noted that the diameter of the seal is larger than that of the seal groove, in order to provide an interference fit. In addition, the seal groove and seal are different in section so that when bedded, the seal feels proud to the touch at the edge furthest from the bore. This is normal.'
What I should have said is that the build up will cause the seals to be “too proud” and hence too tight.

That’s an interesting method advised by AN. I’ve never done it that way myself, but I always check the edges and if there is any hint of sharpness, use some fine wet or dry to remove it, then use brake fluid or rubber grease to lubricate the seals before installation of the pistons.
 
Today was a good day for me. I finally got my Interstate going properly again after burning out my wiring harness last year. My friend on this site Matchless was good enough to rewire it for me as electrics are like algebra to me. I fitted it with the vast Interstate tank (6 gall ?) and side panels (Roadster type) just painted in the white , blue and red by Steve Becket in Sandbach UK. It'll be good to go for a long ride on it again soon. One thing I did wire myself was, - on a Mk 3 if you fit a tri spark mosfet reg/rec the charge light stays on (dunno why as it was charging just fine) any way I fitted one of them indicators that let you know all is ok when engine running and when sitting, I just fitted it in the original charge light hole,having to open it out slightly. If I ever learn how to I'll post some pics.
Yeeehaaw.
 
Today was a good day for me. I finally got my Interstate going properly again after burning out my wiring harness last year. My friend on this site Matchless was good enough to rewire it for me as electrics are like algebra to me. I fitted it with the vast Interstate tank (6 gall ?) and side panels (Roadster type) just painted in the white , blue and red by Steve Becket in Sandbach UK. It'll be good to go for a long ride on it again soon. One thing I did wire myself was, - on a Mk 3 if you fit a tri spark mosfet reg/rec the charge light stays on (dunno why as it was charging just fine) any way I fitted one of them indicators that let you know all is ok when engine running and when sitting, I just fitted it in the original charge light hole,having to open it out slightly. If I ever learn how to I'll post some pics.
Yeeehaaw.
Pictures!
 
Pictures!
Any regulator you fit is likely to have the same problem. The MK3 assimilator needs a feed from two legs of the stator and it needs a plus and a negative and a path through the regulator.

IMHO, throw away the silly assimilator and install a Don Pender oil pressure switch to light the red indicator. The assimilator (MK3 or before) is not a "charge" indicator. It simply tells you that the rotor is spinning in a stator enough to provide AC voltage enough to heat a bi-metal strip. Whether that is enough to be converted to DC charging voltage or even if any of the other charging components are working it has no clue.

Don has them in stock and for US owners, I do too.
 
Any regulator you fit is likely to have the same problem. The MK3 assimilator needs a feed from two legs of the stator and it needs a plus and a negative and a path through the regulator.

IMHO, throw away the silly assimilator and install a Don Pender oil pressure switch to light the red indicator. The assimilator (MK3 or before) is not a "charge" indicator. It simply tells you that the rotor is spinning in a stator enough to provide AC voltage enough to heat a bi-metal strip. Whether that is enough to be converted to DC charging voltage or even if any of the other charging components are working it has no clue.

Don has them in stock and for US owners, I do too.
I believe the MKIII came with 3 different types of assimilators. Early versions had the can type, that only uses one wire from the stator. The solid state US and solid state Canadian model uses two wires from the stator.
 
Hi Rob, when I went 18/19 the 18 was a practical decision based on the availability of dedicated rear tyres but when I fitted the wheel I didn’t like the look but thought it would grow on me but it didn’t. Anyway I was in my workshop and looked at the bike and decided it had to go so ordered a tyre and text the wheel builder to order a rim which will be built by next weekend. In a nutshell the aesthetic, in my eyes, had the look of a custom bike and I just didn’t like it.

Dave
Picked the newly laced 19" rear up this morning, fitted the tyre and put it back in the bike. I’m happy for two reasons firstly, I prefer the look and secondly I took it for a spin and part of the route was along a dual carriageway with some shallow ruts that made the bike feel unstable with the 18" but with the 19" I didn’t notice any tendency towards instability. An unexpected benefit but I’ll take it, I suspect it has something to do with both tyres now having the same profile so one tyre isn’t trying to climb a rut before the other but I’m only guessing.

18" bits will be in the for sale section shortly.

Dave
What Did You Do With Your Commando Today?
 
Any regulator you fit is likely to have the same problem. The MK3 assimilator needs a feed from two legs of the stator and it needs a plus and a negative and a path through the regulator.

IMHO, throw away the silly assimilator and install a Don Pender oil pressure switch to light the red indicator. The assimilator (MK3 or before) is not a "charge" indicator. It simply tells you that the rotor is spinning in a stator enough to provide AC voltage enough to heat a bi-metal strip. Whether that is enough to be converted to DC charging voltage or even if any of the other charging components are working it has no clue.

Don has them in stock and for US owners, I do too.
I use the oil pressure from Don that I wired into the ICM unit which also shows that the bike is charging.Have had it on for a few years now and like the way it works.Not rocket science to install and fits into the shell with no drilling.
Mike
 
Yesterday, I fitted a new 23" brake line, installed new seals & SS pistons (using the RGM modified threaded one for the rear) and tied the brake lever to the bars overnight. Absolutely wonderful lever pressure & brake feel now 👍

Also changed the oil & filter and installed some new Champion spark plugs (as I'm trying out a single carb set up).
 
Yesterday, I fitted a new 23" brake line, installed new seals & SS pistons (using the RGM modified threaded one for the rear) and tied the brake lever to the bars overnight. Absolutely wonderful lever pressure & brake feel now 👍

Also changed the oil & filter and installed some new Champion spark plugs (as I'm trying out a single carb set up).
A single carb is a great way of improving the suitability of the stock brakes ;)
 
Picked the newly laced 19" rear up this morning, fitted the tyre and put it back in the bike. I’m happy for two reasons firstly, I prefer the look and secondly I took it for a spin and part of the route was along a dual carriageway with some shallow ruts that made the bike feel unstable with the 18" but with the 19" I didn’t notice any tendency towards instability. An unexpected benefit but I’ll take it, I suspect it has something to do with both tyres now having the same profile so one tyre isn’t trying to climb a rut before the other but I’m only guessing.

18" bits will be in the for sale section shortly.

Dave
View attachment 112662
Looks very nice Dave! I wonder if you have the same photo with the 18", just for a comparison.

Here's mine. Similar...but with a bit more junk loading her down at the time.
What Did You Do With Your Commando Today?
 
Oh yeah, I can see the slight thickness of the 18" rubber on there. Hey, I might be willing to take your 18" leftovers if it's not too much shipping here to the USA. It looks to be in top shape. Message me with the details if you like.
 
Oh yeah, I can see the slight thickness of the 18" rubber on there. Hey, I might be willing to take your 18" leftovers if it's not too much shipping here to the USA. It looks to be in top shape. Message me with the details if you like.
Hi Rob,

They were in the for sale section and have already been snapped up..

Sorry
Dave
 
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Sooo 23 degrees here no riding. Bought a 75 Mk III a couple of years ago that ran well. Some of you find it hard to believe but I left it alone! It would wet sump dam near overnight. Also the electric start made a lot of noise when used, I'd been kick starting it. While other bikes are getting wired and seat upholstered, tear this one apart. See pics of cracked starter sprag, ordered one from Aliexpress $22.50. So while I'm waiting on delivery , I thought I'd remove timing cover expecting to find anti sump plunger stuck. Well see pic of oil pump seal, it's split! Both sides of this bike could have been very expensive!

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