1962 650ss Build

I've told this story before lol. I parked my Rickman Trident on the slope at Cadwell Park holding area, waiting to be called up for my race. Bump started the bike down the hill as the previous race ended. Small home made tank, did my sighting lap, it was a 6 lap race & the bike cut out at the end of the back straight on the final lap!
Gutted! Quick trip in the van. I found I had no fuel! Next race I was greeted by the marshals with " again? Did you miss us!"
I had done the MV owners club track day, loads of laps & no problems. Serviced the bike ready for Croft (& purchased an alloy TZ tank) & found nearly as much fuel as oil in the sump. Proper washed bores lol
Never understood why petrol taps on race bikes are impossible to find with gloves on.
 
The saga continues, and possibly onto a better path.

So, new updates. The new carbs are nice, and look nice. I do not think I am having a flooding issue anymore so thats great. I was still having a lot of problems with starting the bike. I would get a few pops here and there, or it would turn over maybe 10-15 revolutions then kind of die off.

Tightening up the clutch springs did help with the starting issue. But looking at the plugs, they didn't smell of fuel.

Other thought I had was that the Rotor was not centered within the Stator, and it might be rubbing, and preventing the engine from freely revolving, causing it to stall. This was a problem when I first put the motor into the bike, and I could not kick it over. Taking it apart this evening the rotor definitely has some mildly deep grooves cut into it. So it definitely was not square with the stator, and not at the proper gapping. I also noticed that the stator housing was a bit loose. I'm getting nervous about properly tightening this housing down, I really don't want to strip out the threads in the cases. Not sure what I can do to lock these screws up. Kind of sucks that they're just flathead screws, and shallow ones at that.

Under the urging of a friend, the timing at this point should be double checked. Just to rule it out as the last possible fault of why this bike is not running as it should. Especially given the fresh carbs.

This time around I'm using a much better degree wheel. When I first build the motor I used the Andover one, and it's kind of a POS. This wheel locked onto the rotor nut is much much more accurate looking. I used the spark plug ruler thing just to make sure that I was on the compression stroke. Used a long thin screwdriver to find the proper TDC.

Using the cigarette paper I found that the mag was firing at 27deg Before TDC. So clearly that's out about 3deg.

Standing over the bike, and kicking it through slowly I looked down at the timing side. I noticed that the AAU seemed to be on a slight wobble. Rotating through slowly with the kickstarter I was able to see that the chain tension on the Magneto chain is all over the place. It's clearly not lined up, and the chain goes from about 1/2" slack to pretty much dead tight.

Looking back through some other posts here and the NOC forums, I've ordered the chain tensioner tool from Andover. So I'm thinking that I have to advance the timing a few deg, but also readjust the mounting of the magneto to make sure that the chain runs true. This is bringing me back to my initial issue a few months back when I had the bike out for its first run. Makes sense now if that chain is not running true, that the firing of the Mag would be all over the place once the bike is at running speed.

So guess that my initial issue from all that time ago wasn't fueling after all, and was instead a timing issue. At least, I hope thats the current issue and solution.

Does anyone have any better ideas if I should be looking to just replace the AAU? It returns freely from the advanced position, but it is or does appear to be original, and I'm getting a little ahead of myself suspecting the possibility that the unit is warped or damaged in some way.

the other slight annoyance is that one of the new carbs has a slight fuel leak. Through the bottom where the banjo connects the carbs. I've tightened it up to what feels like a lot, and I'm reluctant to tighten it further. The leak is either from the small cap that houses the main jet, or the joint where the jet holder threads in.

Is it possible that I just need to put fresh washers on? Like if the washers have been over tightened and have failed?
1962 650ss Build
 
Now that`s a degree wheel!

Be sure to check timing on both ramps.

Your description of chain tension reminds me of a post by robs ss. Ultimately, he found his magneto armature was off center, causing the chain tension to vary as the engine was rotated by hand. See https://www.accessnorton.com/NortonCommando/dommie-magneto-chain-tension.22207/

Slick

EDIT: A simple check for a centered armature is to check point gap on both ramps. If the gaps are not equal, something is wrong. The armature must be centered before trying to correct any gap difference.
 
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That is a colorful degree wheel. :cool:

I used to think timing wasn't that big a deal on an old Norton until I set it 6 degrees retarded by mistake. Really not a good thing.

My manual says 32 degrees BTDC fully advanced for the 650ss. If nothing else it should start easier, idle and run better set for 32 degrees all in as long as you use good fuel and kick hard on cold starts. I do think you are on the right path correcting the timing. I should have and may have mentioned getting timing right with that old magneto is a PITA. I definitely thought it, but if I didn't mention it, it was because I didn't want to defend my simple man thoughts to the "test don't guess" police. he he

I don't know your carburetors well enough to say what would stop the leak.
 
Now that`s a degree wheel!

Be sure to check timing on both ramps.

Your description of chain tension reminds me of a post by robs ss. Ultimately, he found his magneto armature was off center, causing the chain tension to vary as the engine was rotated by hand. See https://www.accessnorton.com/NortonCommando/dommie-magneto-chain-tension.22207/

Slick

EDIT: A simple check for a centered armature is to check point gap on both ramps. If the gaps are not equal, something is wrong. The armature must be centered before trying to correct any gap difference.
If the ramps are off (ring needs to be "stoned" or shimmed, won't that also show as unequal point gaps? And if the that's the problem, while the fix is a PIA, it's nowhere as serious as an off center armature. Also, sounds to me like, for some reason, the magneto sprocket and/or AAU might not be sitting properly on the magneto shaft taper?
 
Looking at it for a few hours this morning . . .

Points gaps have been measured and adjusted to 0.012". They are now the same on both ramps. Having the AAU on and off a few times, it was not sitting proper on the taper, I will play with this a few more times to make sure it is square before fitting the cover.

I feel like I had read in a few places that the timing should be closer to 30deg with modern fuel.

As for the carb leak, going to replace the washers and see if that helps.
 
Bodger is correct in that cam ring can result in unequal point gaps. Unequal gaps is due to either poorly machined cam ring or off center cam ring, or off center armature shaft.

Seanalex now reports both gaps are equal which is a very good sign.

Except for assembly with a bit of crud in the AAU female tapere, it is a mystery to me how the AAU can fit poorly on the magneto shaft taper, but that would cause the chain tension problems he reported.

@seanalex: now is the time to rigorously set up and time your magneto. A how to guide is here: https://www.accessnorton.com/NortonCommando/setting-up-and-timing-a-k2f-magneto.19685/

I agree .... with modern fuels, I have set my timing to 30 degree.

Slick
 
I feel like I had read in a few places that the timing should be closer to 30deg with modern fuel.
29 degrees is safer yet.

For some reason (lack of rational thought probably) was thinking an older ignition with an AAU and K2f magneto might work better at 32 degrees BTDC with a lower compression motor and milder cam like yours has.

Definitely go with 30 degrees BTDC if that is what others with the same build are doing. In my experience, the engine build components dictate tuning parameters as much or more than anything else.
 
Bodger is correct in that cam ring can result in unequal point gaps. Unequal gaps is due to either poorly machined cam ring or off center cam ring, or off center armature shaft.

Seanalex now reports both gaps are equal which is a very good sign.

Except for assembly with a bit of crud in the AAU female tapere, it is a mystery to me how the AAU can fit poorly on the magneto shaft taper, but that would cause the chain tension problems he reported.

@seanalex: now is the time to rigorously set up and time your magneto. A how to guide is here: https://www.accessnorton.com/NortonCommando/setting-up-and-timing-a-k2f-magneto.19685/


Slick


I won't be able to get back into it until tomorrow night at best, for some reason work keeps getting in the way. I've consulted that thread about the Mag rebuild about 50times. Actually have it saved as a tab on my phone, so I can reference the sequence.
 
Still waiting on delivery from Andover for the timing support tool. For some reason takes me about 2 weeks to get Andover deliveries. RGM and Norvil seem to ship overnight, should have ordered from them.
 
Still waiting on delivery from Andover for the timing support tool. For some reason takes me about 2 weeks to get Andover deliveries. RGM and Norvil seem to ship overnight, should have ordered from them.
Waiting is tough. AN changed one of the shiping methods or renamed it. My last order took 2 days longer than orders did last year, and maybe right at the beginning of 2022. The name change seems recent to me. Something Force for using Royal Mail. They do still offer DHL, but DHL has in my opinion ripped me off with more charges once things show up in customs in the states, so I used the other shipping choice.
 
Waiting is tough. AN changed one of the shiping methods or renamed it. My last order took 2 days longer than orders did last year, and maybe right at the beginning of 2022. The name change seems recent to me. Something Force for using Royal Mail. They do still offer DHL, but DHL has in my opinion ripped me off with more charges once things show up in customs in the states, so I used the other shipping choice.
I'm guessing you mean "parcel force" or as we know them "parcel farce "
Nearly everything I've had lost or damaged has been with parcel farce
I was having a frame delivered and they dropped it out the back of the lorry ,it landed on the headstock making it D shaped where the bearings fit
Another time they reversed over a petrol tank that I'd bought from America !!!!
But usually they just lose things
One notable thing they lost was a nos t160 primary chain !!!
 
I'm guessing you mean "parcel force" or as we know them "parcel farce "
Nearly everything I've had lost or damaged has been with parcel farce
I was having a frame delivered and they dropped it out the back of the lorry ,it landed on the headstock making it D shaped where the bearings fit
Another time they reversed over a petrol tank that I'd bought from America !!!!
But usually they just lose things
One notable thing they lost was a nos t160 primary chain !!!
Parcel Force is the one.

My package arrived but looked like it was mistaken for a football at some point. Smashed at both ends. Nothing was damaged inside.

Thanks for the info. I might choose to use DHL next time.
 
Parcel Force is the one.

My package arrived but looked like it was mistaken for a football at some point. Smashed at both ends. Nothing was damaged inside.

Thanks for the info. I might choose to use DHL next time.
I had a temporary agency worker working for me a few years ago
He'd previously worked at a parcel force depot
But he was only there a morning
He was so sickened by the treatment of the parcels
 
finally got the pieces. Arrived basically wrapped in duct tape, and wild, took like 2+ weeks to get here.

I know some have issue with DHL shipments into the states getting held up/delayed/sent back. I must be in some sweet spot with their delivery range in the US, because I feel like I get DHL shipments within 3 business days, sometimes sooner.

Regardless, chain tensioning tool is here, and fit. Staring at this thing and struggling to remember what I even needed it for. Chain to the AAU definitely has loose spots and tight spots. I'm thinking that now that I have this tool, I should slacken off the cam nut, and use the tool to help align everything.

beyond that, another stacked weekend doing odds and ends, so regretfully I won't get this back together probably till end of next week.

I really love how this is about to become my winter project. HA!
 
Not much new to report unfortunately.

The past few weeks have just really gotten away from me. Too much work during the week, and too much hosting on the weekends.

Before I do put everything back together and go for the start, I'm going to check the timing on it one more time now that everything is torqued down with the timing now set properly, and the chains on looser tension. The other half of this is I'm going to ditch the Scitsu tach, and put on a nice vintage ATRC tach I got about a month ago. So in this whole setting the timing chains process, I've swapped out the camshaft nut for one that can drive the tach, and purchased a drive unit for the tach. I already had a fresh new cable. Checked it with a drill and the tach spins nicely, so should work and look properly on the bike. Current thing is to fabricate the mounting bracket so that I can hold the tach in that rubber band ring that the ATRC needs. I'm driving to enlarge a hole into an old converta mount that I had. Editing this to read: spent a few hours today trying to perfectly round out the inside of the converts mount, and it looked horrific. I got at it with a hacksaw and a Dremel, had high hopes that I could massage it out. Just ordered a proper bracket for the ATRC from Mr. McIntosh in NZ.

A big problem that I'm also having (mechanically) is in setting the gap of the rotor/alternator. Any solid advice on how to get this thing to float properly would be much appreciated. I originally had done it with a beer can cut to a shim. I think it was close to floating, but it still rubbed.
 
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Hosting is more fun than wrenching. Work is work.

Can't really help with I've done that knowledge regarding the stator alignment. Mine is always dead nuts aligned. Stator is a tight fit in the primary outer case, and Norton or Matchless got it right. The thickness of the plastic used for gallon water or milk jugs might work for alignment shimming. Commando owners will have ideas that will get you in the ballpark. Some guys get the rotor diameter turned down to make the job a little easier.
 
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