So much of this is a learning process as you go along, but carry on. This is an interesting subject.
Oldboyracing 1973 Triumph 750 Chopper.
- Thread starter Oldboy
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Oldboy
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I actually sold one of those cool Webco finned primary covers to a Danish guy once. I wanted to use it so badly, but it would not clear my 32mm 750cc drive belt kit. I could've cut a spacer, but in the end I wanted all the covers finned or not, so it was not. He appreciated it greatly.
Oldboy
Well-Known Member
Did you have any luck finding the chopper man?
I finally ran down the guy with the Tri. chopper but it wasn't a what i had heard, it turned out to be a Norton Commando he had bought new, a Tri. Tiger Cub and a 1968 Bonneville all original and unmolested all 3 for $3500.00, only problem is that he had sold them at the end of last summer. I am now trying to find the guy that bought them but he probably knows what he has. A day late and a dollar short! Close but no cigar!
Oldboy
Well-Known Member
When I was in high school in the 70s there were 2 Norton choppers up the street parked by the curb. I don't even know if they ever moved. But I was fascinated by them. They are what started me on the chopper path. Then as a sophomore I would go to the library in school every day and read thru the Choppers and Big Bike magazines, looking at bikes and thinking about when I would be able to build one. I bought a B*A 650 from my uncle that year and was looking forward to building it. My parents must have found out, because it disappeared soon thereafter. I would still like to build a Norton chopper on an Amen Savior frame. At this point it may never happen. But still think about it.
I do have a belt drive for one though.
I do have a belt drive for one though.
I am always looking for a old HD, Tri. or Norton, just about everything is gone now but i still have faith!
Oldboy
Well-Known Member
There is still a bunch of stuff out there, I saw a guy a while back on CL selling Triumph project bikes, he had several including some set up as MX bikes. Saw one in Washington state set up similar to mine, with girder and prism tank. Also these guys on eBay seem to never run out of new bikes to part out. Makes me wanna scream. What part of the country are you in?
Oldboy
Well-Known Member
The world may come to an end! I have made forward progress. The head is now officially together again. I was wandering around eBay and ran across a shop in Michigan that had a set of Precision Machining (before they became Kibblewhite) Racing valve spring set. It has the alloy upper collars and retainers, steel lower collars and a set of inner and outer matched springs. There was one catch; they were for a 650/750...... Norton.
I didn't let that deter me. After much research (and no small amount of guesswork) I decided the specs were close enough to make them work. The stem diameter is the same. The springs were about .020 taller, which I could make up by removing the shims under the lower collars. The Directions (I read them) said to cut the area on the Norton valve stems where the keepers go to a certain dimension, which was within a couple thousandths of an inch over the dimension that the Triumph stems were already. All I have to do is check coil bind and spring pressures before assembling the top end and I am moving forward for the first time since my assistant and best outdoor Cat Buddy Shawn O'Malley passed away last fall. He was the one who ran the machine shop in my bike shed (read; grinder, hammer, tape measure and bathroom scale). In other words, the brains of the operation. Below are photos of the finished? head.
I am so amazed by the fact that the head is finished, I may go as far as completing the primary side next month when my fresh infusion of funds comes in.
I also located another machinist, my old friend Joe Pape. He has a small engine (motorcycle) machine shop in his garage. He worked at one of the local machine shops, but went into the custom car trade a couple years ago. I located him, the parts store/ machine shop owner where he worked at passed away a couple weeks ago and he may be buying all the equipment. I also found out I can use Norton 850 cylinder liners to reline my Dunstall cylinder, so I can buy both liners shipped from the Land Down Under for about $145. That will be my next big purchase.
Thanks for listening, this is the Oldboy signing out.
I didn't let that deter me. After much research (and no small amount of guesswork) I decided the specs were close enough to make them work. The stem diameter is the same. The springs were about .020 taller, which I could make up by removing the shims under the lower collars. The Directions (I read them) said to cut the area on the Norton valve stems where the keepers go to a certain dimension, which was within a couple thousandths of an inch over the dimension that the Triumph stems were already. All I have to do is check coil bind and spring pressures before assembling the top end and I am moving forward for the first time since my assistant and best outdoor Cat Buddy Shawn O'Malley passed away last fall. He was the one who ran the machine shop in my bike shed (read; grinder, hammer, tape measure and bathroom scale). In other words, the brains of the operation. Below are photos of the finished? head.
I am so amazed by the fact that the head is finished, I may go as far as completing the primary side next month when my fresh infusion of funds comes in.
I also located another machinist, my old friend Joe Pape. He has a small engine (motorcycle) machine shop in his garage. He worked at one of the local machine shops, but went into the custom car trade a couple years ago. I located him, the parts store/ machine shop owner where he worked at passed away a couple weeks ago and he may be buying all the equipment. I also found out I can use Norton 850 cylinder liners to reline my Dunstall cylinder, so I can buy both liners shipped from the Land Down Under for about $145. That will be my next big purchase.
Thanks for listening, this is the Oldboy signing out.
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Oldboy
Well-Known Member
Well, I figured things were going too well, so I thought it was time for a setback. A few days ago I was in the shop and a series of events occures that caused an accident. The end result was a broken piston skirt on one of the irreplaceable Arias forged big bore pistons. Well not irreplaceable, just not unless I replace both of them, twice. For $700.00 or 2 for only $500.00. I am searching for alternatives and may have one, but I cannot say until it is in hand and my final measurements are done. I knew my forward progress was too good to be true. It will be about 2 weeks before I receive the new pistons and can make another report.
On another note, I curbed the wifes scooter avoiding a cat a couple days ago. I drug my shin along the curb for a couple feet with my foot under the bike. I will be getting the bill for the curb repair soon. I didn't know my shin was that tough.
Till next time, cheers from Illinois, the Bunghole State.
On another note, I curbed the wifes scooter avoiding a cat a couple days ago. I drug my shin along the curb for a couple feet with my foot under the bike. I will be getting the bill for the curb repair soon. I didn't know my shin was that tough.
Till next time, cheers from Illinois, the Bunghole State.
Sorry to hear about this set back and sorry to hear of your cat - astrophic accident. Glad you were not too badly injured.
Oldboy
Well-Known Member
Thanks, I appreciate the sympathy on the cat and the setback. I would take a hundred setbacks to have her back. She loved and trusted me, I can replace the pistons but not her man. Thanks again.
I understand completely!
Oldboy
Well-Known Member
In a buying spasm, I purchased almost every engine fastener available on a Triumph Twin made from titanium from Vintage Titanium Spares. He even made custom clutch adjuster nuts that have a hex bolt style top like some old Triumph Super Cub clutches.
I needed some new bolts anyway, and it was no more expensive to go with titanium.
I bought a COMPLETE head bolt set including extra center bolts in case I use a 750 style cylinder, and all the studs to hold the bottoms of the rocker boxes and the head steady bolts for around $150. This was last summer, so I cannot attest to that price today but the owner is a hell of a nice guy and I would buy anything he can make for my bike from him. I am waiting for news on Titanium Rocker shafts, he used to make them and may do it again. I am also asking (begging actually) for him to make Titanium Rockers but he is behind on other projects so it may be a while.
I realise I may be the only guy here insane enough to buy a pile of Titanium parts for a chopper, but its my brand of crazy and nobody can take it from me.
This is my 2021 update. Unless I get off my lazy old butt and do something I will update again next year unless the nutballs in Congress take the last of our liberties and flush them down the Chinese shitters they paid 50× more than they are worth.
Sorry, I know this is not the political forum. It is, however the Freedom forum and I hope I can keep mine. Thanks, Oldboy
I needed some new bolts anyway, and it was no more expensive to go with titanium.
I bought a COMPLETE head bolt set including extra center bolts in case I use a 750 style cylinder, and all the studs to hold the bottoms of the rocker boxes and the head steady bolts for around $150. This was last summer, so I cannot attest to that price today but the owner is a hell of a nice guy and I would buy anything he can make for my bike from him. I am waiting for news on Titanium Rocker shafts, he used to make them and may do it again. I am also asking (begging actually) for him to make Titanium Rockers but he is behind on other projects so it may be a while.
I realise I may be the only guy here insane enough to buy a pile of Titanium parts for a chopper, but its my brand of crazy and nobody can take it from me.
This is my 2021 update. Unless I get off my lazy old butt and do something I will update again next year unless the nutballs in Congress take the last of our liberties and flush them down the Chinese shitters they paid 50× more than they are worth.
Sorry, I know this is not the political forum. It is, however the Freedom forum and I hope I can keep mine. Thanks, Oldboy
Hope you stick around MUCH longer.
Yes don't go any where..........
