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Thread Like Summary
Allan G, GrandPaul, Hillbilly bike, kevin, Noe, WordMan
Total Likes: 12
Original Post (Thread Starter)
#825693 10/05/2020 6:33 PM
by WordMan
Ladies and gentlemen, based on my two previous posts, I thought I would start a third wherein we could discuss what I have learned, what I have planned, and where I might be slightly crazy.

Okay, really crazy.

The Bike:
-1969 TR6R frame
-1977 Yamaha XS650 front forks
-Flanged alloy front wheel
-XS650 dual disc
-Stainless spokes
-Box section swingarm
-Flanged alloy rear wheel
-Stainless spokes
-TR6C foot pegs
-520 O-ring chain
-Ikon Shocks
-Reproduction gauges
-Euro bars
-XS650 switchgear/twist grip
-5 gallon tank
-Stock fenders

-MAP 76°, 89mm stroked billet crankshaft
-MAP 1065N cams (?)
-All new bearings, etc
-Morgo Rotary oil pump
-Long-rod, Triples Rule "big bore" nikasil barrel
-10-stud T140 head
-Tri-Spark ignition system
-Twin plug head (?)
-Mikuni Carbs (32mm? 34mm?)
-Belt Drive (MAP or Newby?)
-Reed valve breather system
-180 watt alternator
-Roadstercycle regulator
-"Stock" 1969 pipes
-"Stock" or repop closed mouth Dunstalls
-Norton style spin on oil filter

Thoughts? Comments? Something I missed?
Liked Replies
#825737 Oct 5th a 10:57 PM
by NickL
For the road, the words 'money' and 'sense' come to mind, but it's your bike, go for it.
Myself, i know my license would last about 20 minutes, i was bad enough with my old
'lively' morgo one. That got detuned as i came closer to being banned and with all the
radar and camera stuff around now i wouldn't stand a chance.
Join a club and go racing, that way you can use it properly and you'll find out how good
it and you are.
The other most soul destroying thing with these builds on the road is coming across
a modern bog standard 650 or smaller modern bike, that just walks away from you
at the traffic lights.................
2 members like this
#825766 Oct 6th a 01:00 AM
by WordMan
Originally Posted by reverb

May be add a direct feed to the crankshaft. My 79 have this adaptation.
Add double front discs.
Add a fifth gear box.

--You had a Triumph motorcycle; at least in that photo; now you want to have a bitsa...with all those Yamaha parts and Mikunis. There are not so much better to see any difference on the road (I have 32 Mikunis) and you will kill the beauty of a real Brit bike.

-Also, I do not understand why to have a piston that rise to TDC before the other can make that bike in an speed demon at road speeds...

If you do not like to race with the bike and you are not a Sunday tourism biker; well; would be difficult to have the feedback that you want in this forum about all that mods to perform on the freeways.

Son, that's a bitsa. That's a '69 TR6R frame, a '73 T140V engine, and a set of late model disc brake forks.

Ran a Yamaha dual disc front end for quite a while before I took the bike off the road. Frankly, when I was done with the Yamaha front end, it looked more "correct" than that late model ever did.

As it sits, now, Note the black lowers, Triumph headlight mounts, and '69 style gators.
[Linked Image from]

The offset won't make it a "speed demon," but it will make it live better and better to live with by making it smoother. Less vibration means less fatigue on both the motorcycle and the rider.

As for money, it's all stupid. I'd be better off financially to go buy a new T120. But I don't want a new T120, I want to build my own bike in the same way I have built for me or my father several vehicles.

Like a '56 Chevy with the front sub frame from a '79 Firebird, an LY4 out of a '96 Corvette (new when we built the car), 700R4, custom HVAC from a '68-'72 GM A-body, tilt wheel (not from a kit), customized dash, power windows, power vent windows, power seat, power locks, alarm with remote start, Cadillac trunk pull-down, custom interior, and a host of other stuff, all meant to make the casual observer think the car was basically a stock '56 with an engine swap (photos from when the car was for sale a few years ago).

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Or, there is the '59 Impala we built with an L99 (LS3/6L80E), disc brakes, HVAC from a '68-'72 GM A-body, custom interior, custom console, etc:
[Linked Image from]

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Or my beater, an '89 Grand Wagoneer with an LY5/4L60E, HVAC from a '68-'72 GM A-body, cruise control, etc (with over 60K since I did the swap). The body and interior are ugly (for now), but the vehicle has been dead nuts reliable.

[Linked Image from]

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Or the '72 "442" I'm building with a 454, electronic fuel injection, Richmond Gear 5-speed, C6 Corvette Z06 brakes, IRS from a Lincoln Mark VIII, tilt-telescopic (not a kit), custom interior, etc:
[Linked Image from]

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The rear spoiler show here is 100% made by me:
[Linked Image from]

So, yeah, I get it, I'm "wasting money" which would be "better spent" elsewhere. Except, not for me.
2 members like this
#825699 Oct 5th a 07:01 PM
by kevin
twin plugs will let you run 87 octane every day
1 member likes this
#825731 Oct 5th a 10:39 PM
by Adam M.
Adam M.
Achieved the same with a stock A65. Perhaps you should research them as well? smile
Seriously MAP 76 crank with their rods make sense. Better check if they have everything in stock before committing any money to this project.
1 member likes this
#825736 Oct 5th a 10:54 PM
by WordMan
Originally Posted by Jon W. Whitley
Originally Posted by WordMan
No, you cannot use the 10 bolt head with 9 bolt barrels.

Sure you can. You plug the 9th hole and drill the new 9th and 10th holes.

I have mated the two in the past and found the pattern totally different. That's the way I remember it but if I am wrong, then so be it.

If you can successfully fit a 10 bolt head to your 9 bolt cylinders, then go for it. Why ask if you already know the outcome ? If you can, then please post a detailed fitting process here for everyone's benefit, who may be so inclined.


I don't think I made myself clear (based on your reply).

The holes don't line up. You plug the current "ninth" hole with an aluminum "bolt" and permanent Loctite. You'll need to spot the head of the bolt flat with the top of the cylinder, then you drill the new "ninth" and "tenth" holes (the "new ninth" slightly overlaps with the "old ninth").

All the rest of the bolts are in the same place, so no issues there.
1 member likes this
#825765 Oct 6th a 12:50 AM
by NickL
The 76 deg crank will help vibes wise, the original proposal via mr Irving was 76
based on the rod ratio and components of a 650 engine though. You may find
there is a better offset than 76 degs with your proposed parts. I have used 68,
76 and 180 offsets in a norton cranked bsa a65 of the 3, 68 was best power wise
180 was hardest to get smooth so settled on 76 as a happy medium. One of the
most important things regarding the offset is how much stronger it makes the crank.
Balance factors of between 50-62% were tried. 50 at 76 degs was best all round but
i was racing the thing so it may not be the case on the road or in a solo frame.
The stroker will give the bike longer legs on motorways, i know a few guys with 89mm
norton cranks in t140's and they are good. Here though, cops are abundant so my relatively
standard old crates are quick enough for me these days.

Kevin is right about the 9-1/2 stud head used on the early t140's but any engineering shop
worth their salt can weld/redrill/mill as required.
Mark Parker who posts on here has a 90 deg 89mm stroked a65 based hot-rod he has
gone the whole hog and uses a late frame etc. He reports the better side of 85bhp from it.
As i said though, i'm an idiot, if the power is available, i cannot resist using it.

You may find a TTI gearbox a good way to go as well, they do 5 and 6 speed close or
standard ratio setups, nice job i hear.
1 member likes this
#825797 Oct 6th a 03:05 PM
by Stein Roger
Stein Roger
Originally Posted by WordMan
Ladies and gentlemen, based on my two previous posts, I thought I would start a third wherein we could discuss what I have learned, what I have planned, and where I might be slightly crazy.

Okay, really crazy.

The Bike:

How I enjoy this kind of mental exercise! See my totally subjective comments in Italics.

-1969 TR6R frame Great frame, keep it.
-1977 Yamaha XS650 front forks I'd sooner use an OIF front end.
-Flanged alloy front wheel They're nice, light and stiff.
-XS650 dual disc Really heavy and not particularly effective. Easier to find updated T140 items.
-Stainless spokes That's what you get these days anyway, but they're still prone to breakage.
-Box section swingarm Good idea, or you can reinforce the original.
-Flanged alloy rear wheel Yes.
-Stainless spokes
-TR6C foot pegs Yes and no, std pegs are nice when you drop the bike.
-520 O-ring chain Good idea. Not sure if the slim G/B sprocket perhaps wears faster?
-Ikon Shocks Or similar.
-Reproduction gauges Absolutely, better and cheaper.
-Euro bars A matter of preference.
-XS650 switchgear/twist grip I'd sooner use the standard items for a cleaner bar, but yes they work well.
-5 gallon tank Less sexy perhaps but ergonomically nice and very user friendly.
-Stock fenders I agree, hard to improve on the looks anyway.

-MAP 76°, 89mm stroked billet crankshaft I don't like the V-twin feel of the staggered cranks, feels like the engine doesn't run right.
-MAP 1065N cams (?) Never tried them, can't comment, but the best real life cams for these engines are usually the E3134 profile IMHO.
-All new bearings, etc Of course but I wouldn't change the cam bushings unless they're worn
-Morgo Rotary oil pump I wouldn't, there's no benefit unless you're using bigger bearing clearances or a very thin oil.
-Long-rod, Triples Rule "big bore" nikasil barrel Can't comment, but sounds nice.
-10-stud T140 head I guess you can have the barrels threaded to suit? Nothing wrong with a 9 bolt head though.
-Tri-Spark ignition system The ones I've fitted have worked really well, idle like a metronome.
-Twin plug head (?) I wouldn't, it can create more problems than it solves.
-Mikuni Carbs (32mm? 34mm?) I'm partial to Amal Concentrics....
-Belt Drive (MAP or Newby?) Probably nice, but I never bother. Chains are fine.I I've used IWIS big pin duplex lately.
-Reed valve breather system Yes, and can in fact be used with the original disc valve system.
-180 watt alternator Absolutely.
-Roadstercycle regulator Don't know them, but they're probably the same old China items most people sell. Usually good.
-"Stock" 1969 pipes Why not.
-"Stock" or repop closed mouth Dunstalls They used to be popular, but to me the "tear drop" type looks better.
-Norton style spin on oil filter They use a hard to find 16 mm thread filters, but it's easy enough to make a 20 mm adapter.
Thoughts? Comments? Something I missed?

Well those were mine.
I'm building something special myself based on a 1970 TR6. I'm using an old ARE alloy 750 kit and a 5 speed gearbox, and an OIF 71 front with a conical hub. I'm thinking of going for the TR6C get-up with upswept exhaust. I's a budget build so I'll keep as many standard bits as I can. Two reasons, the amount spent on expensive bits are never recovered, and I have other bikes to use for touring, so it'll be more of a "Festival Bike".

1 member likes this
#825710 Oct 5th a 08:19 PM
by triton thrasher
triton thrasher
It’s usually a mistake to disturb the camshaft bushes, if that was part of your “etc.”

The rotary oil pump doesn’t self-prime, which makes me think it’s a liability.

Trispark ignition has a chequered history of reliability.

You are proposing to build a radically altered Triumph engine. If you were a mechanic good enough to make a success of that, you wouldn’t be on here asking our opinion on your list of parts and modifications. I think you have trouble ahead.
1 member likes this
#825992 Oct 8th a 05:17 PM
by WordMan
Well, I decided...

I sent a deposit off to MAP for a 76°, 89mm, "billet" crank.

I'll also be buying their "billet" barrels, for an 840cc engine.

I'll consult with Marino as to the best cam for such an engine.

Marino says it will be January or so before the cranks come in.
1 member likes this
#826189 Oct 11th a 12:33 PM
by WordMan
There has been much work going on in the garage. I still have to finish paneling and run a couple wires (through the ceiling), insulate the ceiling, and install the ceiling tiles. But the bike is on the work stand!

[Linked Image from]
1 member likes this
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