Triumph 500 Bob Job

[LoudPipesSaveLives]

After chalking up a few hundred miles i decided against repainting the tins and to keep the fuel streaks from the crappy sealing cap. . . .
Also got tempted by a spanky Electroline headlight that I converted to LED to be able to get the hi/lo that local regs require.
With the headlight looking all a bit to Buck Rogers, I converted and old Turner Harp mic to a taillight also with led.
Then there is the intake porn from Maund.

Bike is running real strong and is a blast to ride.

Love the lights! Tins can always be done over the winter but it has a cool patina going on with the streaking. I might look into one of those intakes! Glad you're enjoying the bike.

[drumbum]

Bought me this the other day and could double my "investment" if i decide to flip it. It was cheap enough to make it a good base for a project but to complete etc to chop it up. Can't help but size it up for a hard tail though. . . . . . . .

[Dougtheinternetannoyance123]

Nice!,, A65s are artificially cheap right now, actually very cool bikes. That looks 1969-70 to me, Too nice to chop, instead go the other direction, Go cafe racer.
These lend themselves well to a nice corner carver and use all bolt on stuff, and when the market turns it can be back to stock.
More value than a bobber or chopper.
Truth is, very few hardtails of a stock A65 frame look good. I have a bobber hard tailed frame here I can post a pix of,, but MOST look like they are bent in the middle and look like crap.
But those motors can have some balls & Fun factor. Look it up,,, the 1966 BSA Lightning was THE fastest production street bike in the world back in the day. BSA was ALSO number 1 in the world for sales at one time. I think the saying was "1 in 5 is a BSA!"

See: http://www.motorcycleclassics.com/cl...otorcycles/bsa

[LoudPipesSaveLives]

Bought me this the other day and could double my "investment" if i decide to flip it. It was cheap enough to make it a good base for a project but to complete etc to chop it up. Can't help but size it up for a hard tail though. . . . . . . .

Wow, what a beauty! Don't touch it.

[datadavid]

Nice!,, A65s are artificially cheap right now, actually very cool bikes. That looks 1969-70 to me, Too nice to chop, instead go the other direction, Go cafe racer.
These lend themselves well to a nice corner carver and use all bolt on stuff, and when the market turns it can be back to stock.
More value than a bobber or chopper.
Truth is, very few hardtails of a stock A65 frame look good. I have a bobber hard tailed frame here I can post a pix of,, but MOST look like they are bent in the middle and look like crap.
But those motors can have some balls & Fun factor. Look it up,,, the 1966 BSA Lightning was THE fastest production street bike in the world back in the day. BSA was ALSO number 1 in the world for sales at one time. I think the saying was "1 in 5 is a BSA!"

See: http://www.motorcycleclassics.com/cl...otorcycles/bsa


[ATTACH=CONFIG]78635[/ATTACH][ATTACH=CONFIG]78636[/ATTACH][ATTACH=CONFIG]78637[/ATTACH][ATTACH=CONFIG]78638[/ATTACH]

And those bsa's all ran the same crappy copper-lead main bush as the triumph 500. How come they survived with all that extra power?

[Dougtheinternetannoyance123]

Well that bushing debate (Timing side bush) is a long running debate. I could explain my take on it, but thats a seperate topic than this guys very sweet little Triumph wouldnt it?

[drumbum]

Wow, what a beauty! Don't touch it.

yeah, going to keep this pretty much as is to add a "gentleman" to the stable. Lose the indicators, change the mirrors and pop some more forward bars on it, maybe some Norman Hyde's. Will look for something else to satisfy the creative need.

[drumbum]

Nice!,, A65s are artificially cheap right now, actually very cool bikes. That looks 1969-70 to me, Too nice to chop, instead go the other direction, Go cafe racer.
These lend themselves well to a nice corner carver and use all bolt on stuff, and when the market turns it can be back to stock.
More value than a bobber or chopper.
Truth is, very few hardtails of a stock A65 frame look good. I have a bobber hard tailed frame here I can post a pix of,, but MOST look like they are bent in the middle and look like crap.
But those motors can have some balls & Fun factor. Look it up,,, the 1966 BSA Lightning was THE fastest production street bike in the world back in the day. BSA was ALSO number 1 in the world for sales at one time. I think the saying was "1 in 5 is a BSA!"

See: http://www.motorcycleclassics.com/cl...otorcycles/bsa


[ATTACH=CONFIG]78635[/ATTACH][ATTACH=CONFIG]78636[/ATTACH][ATTACH=CONFIG]78637[/ATTACH][ATTACH=CONFIG]78638[/ATTACH]

69 Royalstar. Yeah its a bit too mint to chop. Less than 4000 miles on a complete tear down and rebuild by an older guy 5 years ago. Meticulous in his work. I paid $3500.00 USD for it in local currency. I think I stole it from him really though he got what he was asking for it, very quickly.

[Dougtheinternetannoyance123]

Royal star?? That would be a 500cc version but they shared a lot of common parts so many people switch it up to a 650 top end which is easy to do. It should also be a single carb. Just my opinion,,,, but the day will come that someone would pay decent coin for a bike like that.
Its more of a country roads and Sunday tourer,,Not a hotrod with all the problems that go with that, and some people highly value that.
I have a bike in the shop that the owner passed away but his son wants it still,,, The guy spent a lot of time in South America for work but had to return 30 days per year here in the US.
When he got back in 1973 for his annual US trip he was out of the loop for current events. He had cash and wanted a 500 twin BSA and preferably with a single carb. To him, that was the perfect bike. but he was shocked and amazed to learn that BSA was going out of business, they no longer made 500 twins and he could not find what he wanted. The bike he DID buy is another story entirely,,, but my point here is that I know a lot of people who dont need the hottest bike out there, and just want a nice bike like yours... so,, my suggestion is keep it the way it is.
I can promise that every stop at a gas station or coffee shop you will get tons of attention as well as questions and then the inevitable
"My uncle Bob had one just like that and then Aunt Nancy came along and blah blah blah................" Never fails.
Enjoy it!

[datadavid]

Well that bushing debate (Timing side bush) is a long running debate. I could explain my take on it, but thats a seperate topic than this guys very sweet little Triumph wouldnt it?

Yes, but now he bought one of those engines and might want to be enlightened to its peculiarities😀
My take on them is they may not be that bad at all, if you dont whip them and keep the oil fresh and clean, and i think phosphorous bronze replacement bearings last even better than the stock bearings.

[drumbum]

Royal star?? That would be a 500cc version but they shared a lot of common parts so many people switch it up to a 650 top end which is easy to do. It should also be a single carb. Just my opinion,,,, but the day will come that someone would pay decent coin for a bike like that.
Its more of a country roads and Sunday tourer,,Not a hotrod with all the problems that go with that, and some people highly value that.
I have a bike in the shop that the owner passed away but his son wants it still,,, The guy spent a lot of time in South America for work but had to return 30 days per year here in the US.
When he got back in 1973 for his annual US trip he was out of the loop for current events. He had cash and wanted a 500 twin BSA and preferably with a single carb. To him, that was the perfect bike. but he was shocked and amazed to learn that BSA was going out of business, they no longer made 500 twins and he could not find what he wanted. The bike he DID buy is another story entirely,,, but my point here is that I know a lot of people who dont need the hottest bike out there, and just want a nice bike like yours... so,, my suggestion is keep it the way it is.
I can promise that every stop at a gas station or coffee shop you will get tons of attention as well as questions and then the inevitable
"My uncle Bob had one just like that and then Aunt Nancy came along and blah blah blah................" Never fails.
Enjoy it!

A Gentlemanly Sunday Tourer is fine by me. I have a "Hotrod". BSA is an investment really anyway. Like i said, I can almost double my money straight away if i wanted to flip it. PM me about the timing side bush debate if you have time.

[Dougtheinternetannoyance123]

I was trying not to hijack your thread about your Triumph, but since you are the OP I dont see the harm in addressing it here since you asked.
The same issue impacts early triumph 500 twins as well up to around 67? But how its dealt with is different.

As to the BSA and timing side bush, How deep do you wanna go? I can write a small book on that topic, engine design and operating limits.

Heres my version. The Unit Triumphs 1958 to 67? used a bimetallic bushing on the timing side for the crank mains. They had few issues and eventually Triumph opted to switch somewhere around 1968 to a 650 design on ball bearing on timing side and roller bearing on primary side. (Early 650s ran ball bearing both sides, but switched eventually to ball TS-Roller DS)

Most people dont have that much problems with the early versions on the Triumphs. People argue the reason but IMHO its several reasons.
A) Oil pump design
B) Connecting rod design
C) Low power, when the power went up with the Daytona,, they switched to the other bearing designs
D) Engine casting design and crank design (Width of bottom end, short stroke rods/crank,)

BSA twins,,,,,(Ironically none of the BSA singles from 1940s to 1973 used a crank main bushing to my knowledge,,, the reason is simple as well. Oil delivery. A roller or ball race bearing requires only a fraction of the oil supply a bushing does)

So BSA Twins from 1930s up to 1973 both preunits and unit twins all used a Bimetallic timing side bushing. Be aware that some replacement bushings are defective and people have failures at low mileages. Make sure of what you are buying!

But people will argue the reasons for this design and the merits of it. (Not getting into that too much here) But some feel its a known defect and very popular to modify the engines to take a Triumph style design OR a Needle bearing conversion with redirected oil system.

These mods are not for inexperienced and take precise machine shop skills to do. The tech and how to's are out there and extensively covered on many forums. (See BritBike.com, And several other BSA centric forums) There is also a number of shops offering these conversions as well. I used to believe that was the only acceptable method of running a BSA twin but have changed my opinion over time and feedback from others very experienced in this.

There are some that argue there are MANY auto designs that run a crank on such bearings. I agree. I also build car engines. The issue is design and understand why. A car engine tends to be 4 cyls or more. The more cyls per engine the more smooth it is which is why some cars run a 12 cyl (IE: Jaguar) The more journals there are the more stable the rotating mass. (IE: Load per main bearing).
A vertical twin MC engine with a twingle, or opposed fire or 270 degree fire all are operating only 2 cyls. A twingle is a double fire at TDC and very hard on bearings and vibration prone. A 270 degree crank is much smoother (Hence the Ducati which can rev to high RPMs) but an opposed twin typically has a LOT of crank weight and flex.
If you looked at a stop motion photography or Spintron and what happens at even 4000 rpm you would be horrified. Stuff flopping and flexing all over the place. So the bushing main bearing takes a beating. Only Matchless and AJS got it right and put in a center main bearing to keep the cranks from flexing. Most had machine shop issues and misalignment but once corrected (Blue printed) they work well and that same design is now used in Modern Norton twins.

So, BSA has multiple issues with that bushing. *IF you keep the rpms sane, change your oil a lot, keep the sludge trap clean, check for wear often and dont run the piss out of it the Bushing on the timing side is perfectly fine. However if the motor comes apart it needs blueprinting as with a 40-50-60 year old engine the alloy castings distort and change. The tolerances were never great when new but BSA castings distort often in my experience. You have to check carefully but I have seen misalignment on the crank from side to side by 20 thou in one direction and 40 thou on the cam bushes in another direction and when you tighten up the cases the whole motor locks up.
By careful case blueprinting we got all the assys running perfectly true.

The oil pumps are prone to issues, the rods are all alloy and grow in tolerances (looser) and the whole assy has to force oil THRU a bushing into a rotating crank with a groove on the end. On a end fed crank the oil is pushed straight in the end (Quill feed). If you think about a rotating mass of 19-24 pounds and trying to force feed oil in while spinning at up to 6000 RPMs with two tiny holes the advantage of a quill feed is pretty obvious.

So, you can get into Duty cycle, and service life of the parts. The Triumph factory determined that a 500 unit twin when raced the service life for the connecting rods is ONE 500 mile race. After that they are scrap. (*Source, Triumph speed tuning-Stan Shenton & Doug Hele race team manager interview) So,... Thats why I tell people keep the RPMs low (Try to stay under 5000 RPM and gear it to favor low end torque not high RPM HP) Cruising speed at 70 mph should be 3200-3500 RPM in top gear.

If you want to hot rod a BSA there is several ways to do it. One secret with stock rods is I modify them. Swap in Norton twin steel caps, NEW ARP rod bolts and resize the rods by a good machine shop. The stock BSA rods are ALL alloy and they grow under heat. That means bigger tolerances and less oil film or more of a challenge to keep that oil barrier in the bearing surface.

I am building 2 more A65s for my own collection,, (1965 Lighting clubman, and 1968 Spitfire) and 2 BSA 650 preunit hot rods (1951 Factory race bike rigid 650 with the HOTFLASH mods,, and a 1963 Rocket Goldstar). All of them are going to be running NEW steel H beam rods and a lot of other mods.

But a gentle Sunday tourer like this bike you picked up,,, I would make sure you have good oil flow (Flow is ALWAYS better than high pressure) and I would add a Liquid filled oil pressure gauge and idiot light. I also would fit a Norton style oil filter on the return side. Easy mods and great security. But I wouldnt worry about all the hot rod stuff. If I was rebuilding it, I would make sure the sludge trap is clean, and just blue print all the tolerances and that bike would run forever.

The stock oil pumps if not worn are okay for a low RPM non hot rod, but any serious power you either want
A) 1971-73 Late A65 Cast Iron hi capacity oil pump
B) SRM performance aftermarket oil pump (+ its BLUE!)

Below is some pix of stock crank with the side fed oil groove from the bushing as well as typical sludge trap contents (A clean engine is a happy engine) a stock bushing and oil passages (Small eh?) and a cutaway of a custom end feed and needle bearing conversion as well as a conversion needle bearing installed instead of a bush

[drumbum]

Changed out my bars last week. Not a big tweak in the scheme of things but ties the front together much better IMHO. The narrower bars make it easier to get in and out of my little tin shed as well. Ha.

[LoudPipesSaveLives]

Saw pics of your bike on Maund Speed Drumbum! congrats. I ordered one of those 45 deg intakes tonight.

[drumbum]

So local regulations is for a front fender of some description to be fitted to a motorcycle and while I don't want to fit one there aren't any specs as to what this thing over the front wheel must actually be. So. . . . . i find this cool alloy fender tip off a moped front fender that has a neat thing going on with the headlamp. It ticks the box for local regs even if it isn't really a fender. Will fab the bracket this week and fit on the weekend.