G15-CS Survivor

So I had another thread on my attempts to get a G15-CS running (https://www.accessnorton.com/NortonCommando/matchless-g-15cs-get-it-running.21369/). It has been a while, the pics aren't accessible anymore, and I figured I’d start another, more concise thread with some updates.


Long story short, obtained the bike from the original US owner (friend of mine) in 2016 while I was living overseas; he saw the work I had put into my Royal Enfield (my first bike) and thought I’d be a good next caretaker, which meant a lot to me. He had conducted what he termed a “redneck restoration,” including the solid red paint job, in the mid-90s. Ran when parked…but it had been a while. Due to living and work situations, it’s been hard to get to a place where I could work consistently on it.


All I had seen before I got the bike:

Original by Mick Doul, on Flickr


Picking it up….first view in the garage.

Unveiled by Mick Doul, on Flickr

Astride by Mick Doul, on Flickr

Loaded by Mick Doul, on Flickr

Got home and got to work


IMG_20160626_105541 by Mick Doul, on Flickr


Off the bat, I found the magneto wasn’t working, so had that re-done with the Brightspark Easycap.

The clutch hub was really notched up, and it didn’t seem cost-effective to try and clean it up, so I replaced it. The clutch pressure plate stripped in the center adjuster while I was working on it, so I put on a new, machined repop replacement and some barnett friction plates.

13521075_10208567423755857_1847316690_n_zpsgdetnyga by Mick Doul, on Flickr


The carb slides were also sticking like hell, so I had them sleeved, then rebuilt with new jets and gaskets.


Over an extended period of time, I also installed a reversing cam plate in the transmission so it would match my other bike, which is a right-hand, 1-down pattern. Had the Ceriani shocks rebuilt by a guy I found who’s into that stuff…no one else would touch them, and they appear to work well.

After finally getting it timed properly so it ran on both cylinders, I found the primary was a leak-fest. After multiple attempts to seal it, I installed a Newby belt primary, which was inevitable since I have one and love it on my Enfield. With both bikes, being able to access/remove the primary to get to other stuff without having a wet mess and constant gasket re-fitting was as much a motivation as performance…just wish I’d have ponied up to do it before fixing up the original clutch. I know I could have dressed the gasket surfaces, but it was just a mess I hated dealing with, and the Newby clutch is so much better. Install report here: https://www.accessnorton.com/NortonCommando/newby-clutch-installation-report-g15-cs.29138/


I have found that the swingarm seems like it’s spaced too widely (https://www.accessnorton.com/NortonCommando/g15-cs-rear-wheel-spacer-issue.28979/#post-443070), but after a struggle with my original speedo drive which led to replacement with one of the British-made repops, I just tightened it down. Now it’s rolling without a hitch, so I’m going to leave well enough alone there, for now.

The tacho was also breaking every cable I put in it, so I think that’s due for a servicing. Haven’t yet sent it off yet, but should soon. Was focused on functional items first.

So here I sit now…


outside by Mick Doul, on Flickr

49066399938_e19fc02c7b_k by Mick Doul, on Flickr

I need to do some minor cosmetic work, optimize the brake operation (not good with drum brakes) and get it registered for the road and give it some more thorough shakedown rides, and also get into the forks to see what awaits me there. Previous owner said they had the typical top-out issues endemic to Roadholders, so I’m planning on doing the conversion described on the JSM Motorsports site (https://jsmotorsport.com/technical-fork-damping-sleeves/) assuming what I see inside the fork matches what the site describes. Was considering changing the solid metal fork shrouds out for the original flexible boots, but since the bike is about to be put up for three years in the spring, I’ll wait on doing that till I have the bike back in hand, and might put some of the JSM turcite bushings in at that point too.

Damn thing even has air filters now. The Uni sock filters are a lot less cumbersome than the stock filter, which is a flat, pig-iron cage containing a foam element right at the carb mouth. So in this case, pods are a decided improvement...


78641990_2655037457868013_554311893720760320_n[/url']


Another solid shakedown ride; no one to shoot video of it in motion tho. Atlas engine has balls for days. Brakes, on the other hand...yeep. That SLS front could use some more oomph. Some high-zoot pads and a new cable should help...the one on there is too long (per original owner's notes) and I run out of adjustment trying to tighten it up.

Thanks for the write up. I have one that I need to start on.
As to the front brake, My plan is to use a twin leading shoe brake from a commando.
I believe it will be a straight swap out.

Thanks--that's a good plan and I'll take a look...

Re; “That SLS front could use some more oomph.”

Already covered on this Forum;

https://www.accessnorton.com/NortonCommando/drum-brakes.10690/#post-147362

https://www.accessnorton.com/search/24145979/?q=Drum+brake&t=post&o=relevance

franko said:

Thanks for the write up. I have one that I need to start on.
As to the front brake, My plan is to use a twin leading shoe brake from a commando.
I believe it will be a straight swap out.

Click to expand...

The Triumph TLS is a much better brake. I believe one can make it fit without too much fuss. It will be worth the trouble.

Slick

Thanks all for the info--I think I will try to optimize the SLS before swapping to anything else.

Got inside one fork leg now. Definitely different internals to the regular Roadholder...looking to see what I can do to cure top and bottom-out klunks.

Talked with Jim of JSM motorsports and purchased his aluminum sleeve to blank out the stanchion holes.
2019-12-11_07-58-23 by Mick Doul, on Flickr

However, he's not sure if I need/should be plugging and re-drilling any of the holes in the damper tube, which is different from the regular Roadholders from what I can see online. It has a hole low in the taper, and two more near the top of the tube. Any thoughts? I was inclined to close off the hole in the taper and re-drill slightly higher, intending to preserve a pocket of fluid under the damper valve as it descends under compression...currently it looks like the hole lets all fluid underneath the damper out and might allow the valve to bottom harshly on the foot of the tube. But my understanding of the fork operation is limited; this is my first experience with the plunging damper arrangement vs. the more traditional (to me) pumping rod, so any correction is appreciated.

The damper top cap differs from what I've seen illustrated as the standard Roadholder cap, a bushing held in with a clip rather than screwed on top. Has a pretty snug fit, and the damper rod itself is a smaller diameter (.310) than the .375 I see quoted for Roadholders.

Reference pics of damper arrangement:

2019-12-11_07-59-02 by Mick Doul, on Flickr

2019-12-10_03-38-01 by Mick Doul, on Flickr

2019-12-10_02-37-55 by Mick Doul, on Flickr

2019-12-10_02-40-54 by Mick Doul, on Flickr

Welcome any of your thoughts...

Thanks!

Just got my tach sent off to Mark Bohman for rebuild, too.

Still working on the fork, trying to puzzle out the precise operation as it sits, and what effects modifying it would have.

IMG_20191214_084152617 by Mick Doul, on Flickr

Small holes plugged with set screws with loctite bearing retainer...JSM sleeves installed.

Did some more transmission work today to reduce chances of clutch slip in the future.

IMG_20191219_150755234 by Mick Doul, on Flickr

Also got my tach back from Mark Bohman; he turned it around in about a week for $100, which was quite unexpected. I thought it'd be back well after the holidays. I didn't have him do anything cosmetic, however; just free up the frozen guts. No need to make it stand out from the rest of the world-worn bike, and the dials, needles, glass, and bezels on both instruments are in great shape anyhow.

Also wrapped the stator wires in self-amalgamating tape; the sleeving was flaking and there were abrasions in spots. I considered a more drastic repair of butt-splicing some new wires in, but figured I'd do this first as a least-invasive option.

IMG_20191219_095952897 by Mick Doul, on Flickr

Small updates... My damper tubes got lost in the mail. Given the impossibility of finding the correct parts (030440 Teledraulic style, vice the available 030037 Roadholder internals of post '65 forks), I had to either convert fully to to the later style or find another solution. Have decided to go with the Lansdowne-style damper cartridges, and Don has agreed to make a longer set to match the stanchion length, so there's an interesting development.

Clutch pushrod seal on the way, following a confirmation that it should work with my shortened mainshaft , along with a new pushrod I'll trim to length and round off, leaving as a single-piece unit.

Dampers located by Mike at Walridge for a good price and my forks are going back together.

85023823_197262971683086_7716190591607898112_n by Mick Doul, on Flickr

I would still like to do the Lansdownes, but I will need to wait, as some orthopedic surgery in the family just sucked down a bunch of liquid cash...

85048147_2704978926285631_7420195331196846080_n by Mick Doul, on Flickr

Looks like 5" total travel available mechanically from the fork, as indicated by my red paint pen marks...that's correct, yes? I do have the JS Motorsports anti-top-out collars installed.

Looks like the JS Motorsports sleeves cut down the total available fork travel by about 1/2" or so.

I wanted to see how that compared to the spring travel, so tried to measure them extended and fully compressed. Rigged up a closet hanging pole with a 2x4 across it to compress and measure the change. It worked like a charm, even working solo, balancing myself on it using the wall for support.

Then I decided to double-check for good measure. Ended up with a bent spring when a coil slipped underneath the setup.

So I got relevant measurements to Don and we'll see if those Lansdownes will work after all.

Hoping to have custom 31 1/4" long Lansdownes in my hands on Tuesday...

If I can get the primary buttoned up this weekend (want to reshape the tip of a new one-piece clutch pushrod I made to work with the seal nut and additional clutch plate), I should be ready to get the new fork together next weekend at latest. Once that's done, I'll have a rideable bike with working instruments, plates, registration, and insurance!

Lansdownes in hand! But...they won't fit in my new stanchions. Ugg. Too narrow by a hair.

Old ones work, though. Nothing wrong with them I know of...just planned on replacing the 55-year old, battle-scarred originals since repops were on sale cheap at Walridge.

Will need to ensure no interference between the nuts holding in the bottom bushing and the taper on the cart. The originals use a different style of bushing retention than the Norton circlip.

Edit: new stanchions are fine! Just had a little bit of swarf-y stuff leftover from machining...polished it off with the Dremel and the carts fit fine now.

Now if only the headlight ears on this thing weren't the hardest part of putting it back together. Ugh.

Finally there. Damping at the front end is amazing. The cerianis in back are pretty nice, too, after their rebuild.





A nice pair...haven't had the clocks on it in forever, and the tacho works now thanks to the recent overhaul. Speedo was wacky so I need to check the cable.





I like the Ceriani ears...to me, it looks pretty "desert sled" in their incongruity with the fatter lowers. Need to put some black silicone at the shrouds under the clamp to keep water from running inside and then collecting. Drilling the lower shroud for some drainage might also be a good idea.





Best part is the Stig loves her improved passenger space over the Enfield.



Lots of little things to keep tweaking, but now I have a running, plated motorcycle!

Wow, I'd better point that headlamp at something terrestrial...!