PUCH 250 SGS

Restoring a barn-fresh 1966 Sears Allstate

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1974 850 Norton Commando

This beauty is for sale, 1974, 850 Commando.

  • New rubber, Avon Roadmaster TT100
  • New Boyer digital ignition – first kick start
  • Dual Amal carbs in good condition – steady low tick-over
  • lots of chrome
  • stainless fenders
  • recent paint
  • matching numbers
  • Steel tank
  • new battery

Will be at CVMG rally in Paris for sale!

posted by Fastback in cool bikes,mechanical,Norton Commando,restoration and have No Comments

Amal tips

Amal - high speed modI had my Amal concentric carbs sleeved by Bruce Chessel of Woodstock ON – it was the best thing I’ve done for the bike. Sleeving the carb is actually a bit of a misnomer as it is the slide that gets sleeved, the body is just bored out and the slide is sleeved in brass to prevent galling from like metals.

I stumbled upon this service bulletin in a forum the other day and thought it worthy of reposting. My 750 commando is so thirsty at WOT that i need to open both fuel taps to keep the engine from stumbling – perhaps this will give a bit more top end?

Here’s a note from Dave Comeau (Atlantic Green Technical Services) when I was running 32mm carbs before I got the original 30mm Amals re-sleeved:

The ’70 model you show on your website, assuming it is the one with carb problem would not have originally been a 32mm. However that is not a big deal that they are not 30mm.
Your symptom of rough running at just off idle/light cruise is indeed….. cutaway.
Raising the needle will have more affect at bigger throttle settings.
If you have combat carbs with 3 cutaway, you will do better if you mod them to 3-1/2 or try them at 3-1/4 before you go all the way to the full 1/2.
IIRC each cutaway # is 1/16″ ,,,,,so a 3 cutaway is 3/16″
1/2 is 1/32″ custom 1/4 is 1/64″

posted by Fastback in mechanical,performance,restoration and have No Comments

bondo, primer, fender, nacelle

IMG_0003_nacelle

filled and primed

At long last I am actually doing some real work on my ’68 Puch 250 SGS. I replaced the oil in the tank with some TC-W3, and I think I’ve burnt off  all the old 10-w30 that was lingering in the system, much less smoky now.

I’ve fitted the choke plate and it works great, the bike is a 2-3 kick start; replaced the lower bolt on the chain guard (flowed the brazing to remove the old bold, re-brazed a new one on; filled holes and primed the nacelle; repaired a crack in the fender, banged out a few of the dents, and slathered on a liberal coat of Bondo.

IMG_0103

removed a rusted/crumpled section out of the headlight edge.

I initially experimented with trying to stick weld the sheet metal, I know it can be done, but it is out of my skill range and I don’t have the time to practice. I did fill one hole on the nacelle  but opted to brass braze the others as it is faster and well within my skill range.

It is hard to articulate just how badly dented the front fender is, it resembles a sheet of paper that has been crumpled and smoothed out again, the shape is there more or less, just very lumpy. This can be seen in the picture where I ground off the paint before the resin filler. I’m using a quick-set filler, must say I love it, really speeds up the fill/ sand cycles.

IMG_0033_fender_bondo

first round of triage

The fender will make a thud sound when finished rather then the nice ringing ding of an all steel fender. I suppose I could buy a less abused fender off ebay, but that wouldn’t be quite right.

IMG_0030_fender_braze

Brazing the crack.

posted by Fastback in mechanical,restoration and have Comments (2)

Twingle motor in a crate.

NOS Puch 250 motor

NOS Puch 250 motor

Ebay listing in Alabama:

250cc Sears Allstate twingle puch motor new in original Sears shipping crate. Includes mufflers and tailpipes, new carburetor, new coil, everything needed to install.

Bidding started at $1,100 with a final selling price of a whopping $1,651.00  USD – with only 9 bids! I gotta say that is over triple what I paid for the whole bike… mind you mine is a bit rusty, but still. I wouldn’t have imagined these parts fetching such a high price.

posted by Fastback in mechanical,parts,restoration and have No Comments

Ameliasburg

Malcolm and I hit the road on Saturday to attend the 23rd Annual Quinte C.V.M.G “Rally and Show”, July 22nd to 24th, 2011 at Robin Lake Park, Ameliasburgh, Ontario. We hit the road at 11:30 and slogged out on the 401 – of course hitting stop and go traffic. Malcolm’s bike wasn’t happy past 4000 rpm on the highway – we think there is dirt in the tank – sputters, coughing and general grumpiness would ensure with attempts at acceleration or WOT.

We finally got off the highway at Cobourg. All was fine until Colborne, when gearing down for a 90° in the town center my clutch cable pulled out of the nipple. Now considering myself a smart fellow, I brought an extra cable, being even more clever it was one of two that I purchased off Ebay as NOS. What better I thought then fit an old bike with original parts!

I fitted the cable with my grossly inadequate tool kit. Malcolm had to borrow a dime from the corner store to improvise a screwdriver to get the lever off. His excuse for not bringing tools was “I figured you were prepared” and in his defense it wasn’t his bike he was riding.  I fitted the cable and off we went. The bike was NOT happy. I couldn’t get the clutch to fully disengage and it required an iron grip, it was actually easier to shift without the clutch then with it.

We arrived at the the campground and were greeted with cold beer and familiar faces. I spent lots of time fiddling with the clutch, adjusting the lower adjuster – when finally it dawned on me to use the spare cable the Malcolm’s bike had. Needless to say fitting the Barnett cable was a dream and the bike was happy.

Long ride home, passed through Trenton, saw the barracks where I spent 2 weeks as an Air cadet.  We didn’t get rained on despite the forks of lightening off in the distance. We pulled into Toronto at 11, almost 12 hours after we left, the streets steamy and wet from the days heat.

posted by Fastback in events/shows,mechanical and have No Comments