Discussion in 'Norton Commando Motorcycles (Classic)' started by comnoz, Mar 22, 2018.
Simple as a rock fight. Thanks for posting this.
The first time you did it that way, how did you determine the length of the spacers that go over the studs ?
I would guess it was trial and error. But since it would have been about 1974 I don't remember.
Edit: so after thinking about it I have to credit my brother in law. I was at his place installing Powermax pistons in my N15. He handed me 5/8 spark plug sockets and told me how to do it. He was a long time flat track racer on Britt bikes.
Thats pretty darn cool Jim. Thanks for sharing.
Its so uplifting-healing-encouraging to see seasoned pro's making it seem so easy. Piston fitting and rod installing has been my weakest task so will finger nail next attempt on Trixie Combat. I tie barrel to spine to dab sealant & diddle pins into rods but not all pins slide in by finger only pressure so not that impressed, if not filling us in on what it took to get such easy pin clearance. If easy pin install is normal then ignore me as your ease don't apply in most my recoveries. Only snapped a ring once with hose clamps but happened so easy-unexpected like glass, I see your finger diddle wisdom. I've wood dowel to align hole and assist stubborn pins with care not to side load rods much.
I don’t do it that way for one very simple reason: I’m too clumsy!
I once did it on an OIF Triumph and, even though I used a rag around the case mouth, I still managed to drop a clip, and in looking for it in the folds of the rag, I dropped it into the motor.
So, I removed the barrels again and got my head in the frame loop space, holding a small mag-light torch, peering into the cases looking for the clip...
Then I dropped the torch in there too!
I managed to get both out eventually, after quite a period of cursing and some fiddling and some grazed fingers...!
Murphy’s Law: Whatever can go wrong will go wrong.
Now that made me laugh ;-)
Fantastic Jim, I'll use this method when I'm re-fitting my barrels
The pins slide in easily with most cast pistons. Not so much with forged pistons as the pins have to be fit tighter. For them I put the pistons in the barrel and then put a heatlamp over them for a while. Then the pins slide right in. Jim
I bought a good pair of ring compressors once and made a nice u-board from ABS. I used it a for a while and ended up with slightly bent oil rings a couple times. Of course I didn't know it until the engine used oil on one cylinder.
The compressors and board are now tucked away in the toolbox, unused for many years.
I have been selling a second set of rings 2 or 3 times a year to replace the rings damaged on assembly. After explaining how to do it on the phone too many times I decided it was time for a video.
often feel I picked or stumbled into wrong hobby horse as learning/running into miss fitting parts and fumbles set me back weeks to years. I'm forced into mechanics so admire those able to face the cascades of failures till successes. A coulpe seasons ago merely needed to put barrel/pistons on, got the hardest first pin in with mild resistance so relieved elated pushed the other one in pretty easy .... all the way past far circlip end point beyond piston.... I felt like a monkey seeing a magic disappearing act, stunned then angry being tricked. Its was nowhere outside engine so took a few weeks to collect friends to flip Trixie over with pounding on cases and turning engine some in hopes clip would fall out but must of evaporated so ordered more but cylinder got dropped/busted on next attempt so undetermined recovery again.
I spritz rings/bore with wd40 solvent and a dusting of Bonami for smokeless seating about 15 sec after oil pressure reaches head so 45 sec total but carry on gritting teeth with rpms on cam/lifter concerns. If its gonna blow better to start next recovery clock going sooner.
I think you just took the ‘Clumsiest Wrencher’ title from me Steve.
I have to try harder....
I am very very impressed by Jim's method, and it makes me wonder if it could be extended to locating push rods with head and block off the engine? This was a once favoured NOC method , never appealed I thought the extra weight of the head on the barrel
would be more than one person could steady when pushing the ringcompressors off
It works on a 750. Can't do it on an 850 with the barrel through bolts. Jim
Thanks Jim , fortunately I have a 750
Very Cool Jim,
Thanks for posting this vid.
Why would the through bolts on an 850 be an issue as they dont go in till the cylinder is sitting on the case anyway. I got a 750 with aftermarket through bolt cylinder and I cant see why it wouldnt work, or am I not seeing something. Which is entirely possible by the way.
The guys are talking about a method whereby the head is bolted to the barrels BEFORE being bolted to the cases.
With a through bolt barrel, this is impossible as the through bolts must be tightened into the cases before being covered by the head.