Unfit for use

THERES A THING , below .






NOTE : the adequate fuel flow requirements ! Both Taps Open on a Triumph @ W F O or itll burn out .



Think Terry McDonald is the Thruxton bits bloke . Evenif he finks 8000 rpms out of hand . Not to mention 8500 . https://triumphbonneville120.co.uk/tt-specifcations.php

If a outfit does the center boreing , You MUST mention its offset or the might center the tappet block overbore where it is now . useless .

https://triumphbonneville120.co.uk/tt-specifcations.php should be les Williams ? https://www.facebook.com/lpwilliamsltd/

Morgo Thruxton Tappet Block.​

$75.00 Regular Price
$54.95Sale Price


Morgo Thruxton Tappet Block.

Morgo tappet blocks are made from S.G. material to give more resistance to wear and lug failure. Precision made to very fine limits these tappet blocks will give long and trouble free service.

Thruxton tappet blocks can only be fitted into a cylinder that has been machined to take the larger diameter body of this block and requires thruxton followers.





Unfortunataely , youll then need a set of Thruxton Cam Followers .



or altenately , re fit the hole / bore central , oversize , and press in a sleeve to accept the std. tappet block .
a bit of mucking about , but most boring machines have a tilting head or table , so hand opening it to near central & finish boring it
isnt to difficult . some tradesman could even do it by hand tools , like 500 single cam lobes .

I dont think compounding errors is a viable solution . Check the cam lobes lateraly about the crank ( flywheel )& case centerline

A ruler & a good sharp pencil , or blue & a scribe , for starters .

Matt Spencer said:

Morgo Thruxton Tappet Block.

Click to expand...

I'm going to pull and check the cam bushings and the case, and replace the bushings. Hard to know where all the faults lie until it's all been checked. Making sure everything is as perfect as can be before modifying anything is the only sensible approach.

My work (and all parts used) up until this point is certainly worthy of a double check, starting with the cams' reference points of the cam bushings.

Nother Whinge , the Pre Unit 500 ran NEEDLE ROLLER drive side cam bearings . Woulda been built V early 60s , so Std. Tri Part . Photos just for referance .



Gets one wondering as to fitting them to the timing side also . Had drilled & polished 3/8 Timing Gears with a 1/2 in idler gear thrown in , presumeably later .

Good luck with it all . Note Books , Straight Edges , Virneers & pencils called for , no doubt .

Matt Spencer said:

Nother Whinge , the Pre Unit 500 ran NEEDLE ROLLER drive side cam bearings . Woulda been built V early 60s , so Std. Tri Part . Photos just for referance .

Gets one wondering as to fitting them to the timing side also . Had drilled & polished 3/8 Timing Gears with a 1/2 in idler gear thrown in , presumeably later .

Good luck with it all . Note Books , Straight Edges , Virneers & pencils called for , no doubt .

Click to expand...

I think those would certainly be cool, but there would undoubtedly be some custom plain journal (non-scrolled) cams needed ($$$$$). I'm hoping in my heart of hearts that all stock parts will suffice!

Sure is tempting to drill and thin timing gears though...

Got a couple pairs of sintered bronze cam bushings from different manufacturers coming. We'll start with that.

t ingermanson said:

I think those would certainly be cool, but there would undoubtedly be some custom plain journal (non-scrolled) cams needed ($$$$$). I'm hoping in my heart of hearts that all stock parts will suffice!

Sure is tempting to drill and thin timing gears though...

Got a couple pairs of sintered bronze cam bushings from different manufacturers coming. We'll start with that.

Click to expand...

Drill ‘em if the urge takes you but don’t thin ‘em, at least not the teeth, they widened ‘em for a reason.

They probably got rid of those needle rollers for good reason, a bush with oil lubrication works fine.

I did get a set of the US made camshaft bushes but I think it was Dan at Franz and Grubb who said stick with sintered, he has the good connecting rod shells also.

Time Warp said:

They probably got rid of those needle rollers for good reason, a bush with oil lubrication works fine.

Click to expand...

Fast Eddie said:

Drill ‘em if the urge takes you but don’t thin ‘em, at least not the teeth, they widened ‘em for a reason.

Click to expand...

I'm not really going to put in needle rollers or thin the gears, but it sure is fun to think about all the bad ideas! Pretty sure the only successful application I've seen for the thinned gears is sprint bikes.

Yes, the sintered bronze bush is very much the way to go. The horror stories of seized solid bronze bushes spinning in the case is enough to me put me off, no matter who makes them to what tolerance. I got two sets so I could get an idea of a flange thickness, as I don't have a drawing or spec for those. There's some in the cases I replaced (that I bet are original) that I'll knock out and measure as well. Their thrust faces are a bit worn though.

Too many irons in the fire right now. It might be a while before I can get to this. Work is a hurry-up-and-wait scenario at the best of times, and with the Covid supply chain, it's all thumb twiddling punctuated by full blown freakouts of productivity. Weekends are consumed with a house renovation and property restoration. Good thing there are 28 hours in the day.

So, I got a window of free time (!) yesterday to replace the cam bushings and try to get this turkey to fly. As a reminder, the bushings that were in there were replaced by me, but were from a rebuild of another motor years ago that never got used. I don't remember where they came from and had no packaging anymore. I honestly didn't inspect the cases as carefully as I should have either. It's hard to remember all the things to look at that have a bearing on the complete motor.

I tried to get two pairs of cam bushings made by different manufacturers to try and get as many data points as is reasonable, since I don't have a drawing or specs of the bushing. Turns out the bushing sets were both made by LH Harris. Oh well. There goes my vast data point acquisition! I measured them as carefully as I could and there was a bit of variation, both in overall length and in flange depth (on the timing side). The flange depth was pretty hard to measure, since there is a chamfer on top and bottom and the OD is only slightly bigger than the OD of the bushing. There seemed to be a variation from .095" to .099". As I said it was hard to measure accurately with the tools I've got, with a regular caliper being best. I wrote in marker on each of the bushings the corresponding flange depth.

I heated up the cases and knocked the existing bushings out. I measured those and they were both the thinnest flanges in the bunch at .091 and .092". Looking into the inside of the case's bushing flange counterbore. It looked like they had been "cleaned up" or deburred, meaning it looked like the corner from the counterbore into the bore was less than square, which is not great news normally, but great news to me in that if the bushing with a thin flange was sitting deeper into the counter bore, it would cause the cam to locate with a timing-side bias, which is what I'm experiencing. Measuring the actual counterbore depth was all but impossible due the lack of access in the tunnel, and the texture of the inner face of the case, so I just marked it as "deeper" in my mind. The inlet side looked deeper/more molested than the exhaust.

Reheated the cases, and knocked in new bushings, just until the sound changed, and not a touch of the hammer more, using the ones with the deepest flanges in the bunch on the timing side. Reamed 'em out, put the cams in, tightened up the cam gears, and measured the center of the cam lobes in relation to the center of the tappet block bore of the cases and case seams. Dead nuts. Sweet.

I put offered up the barrels to the crank-less bottom end, with the tappet block and tappets installed, and the tappets moved independently on the cam lobes! Sweet. With a possible bias to the drive side now, it's tough to check, since a loosened gear will only shift to the drive side (and not further to the timing side), but the inside tappet faces were about .026" apart, so if you move to the cam to the drive side by loosening the gear a certain amount, you can extrapolate where it sits when the timing side lobe hits the drive side tappet. Once again, the inlet and exhaust lobes weren't hitting the tappets in the computed dead center (or inlet and exhaust same as each other) but both had enough wiggle room for me to feel comfortable that they were close enough, especially with thinner cam lobes buying extra wiggle room on the stock width tappets. I agree the math doesn't quite all add up from what wasn't working to what now seems to be working, but once again, there may be more at play than I'm seeing.

I'm going to run it and see what happens as the dealer has not followed up within a week of my last question of their offer to "walk me through" the warranty protocol directly with Aerco, and moreover, the tappet block bore could very well be within spec and I'll just waste a bunch of time and money being told that it is. I'm going to give another shout over to the dealer and see what their thoughts are. They have not been helpful in any way, so I don't have much faith in them and will not be patronizing them again. John Healey, who imports these reached out and said that in his experience these kits are good and that he would honor any return of defective merchandise outside of any "return window" purchased from him, but that the dealer in question had probably not bought this kit through him. If I were to buy one of these kits (or anything Triumph aftermarket), I would make sure to choose your vendor carefully.

As far as my experience with the Aerco kit goes, it's more obvious to me now that the tolerance stack can be a real obstacle. The locating studs for the barrel are on the opposite case half as (and are oriented perpendicular to) the locating point for the cam. The Aerco barrel seemingly uses a flat, machined on the timing side of the casting, to then drill and bore all the holes that use the opposite case half as it's locating point. With those complicating factors it sets things up to be off a bit, but the tolerances seem to be loose enough where it may not matter, particularly when Triumph was doing all it's own manufacturing and could keep track of all the minutia. When separate parts are machined to loose tolerances (even when those parts are individually with spec) by different vendors throughout the world, there are chances things won't line up. I was taught by all my machining teachers to have as few reference points as possible and try to keep them all oriented the same direction. My biases may be playing into all this, for sure.

The Aerco kit I got seems to be within the acceptable limits to make it work with other parts in the acceptable limits, with a keen eye on variables. I think there was a bit of a "perfect storm" going on here that had conspired against me. That's life...

One problem I also ran into was also due to the drilling of the studs within the off-center casting. Some of the stud holes were extremely close to the barrel wall, so I had to grind down a wrench very thin (!) to tighten the nuts. Yes, they are the proper 12 point, small-head nuts. The drive side stud closest to the inlet tappet block was the closest to the wall, and the wrench had to go down to .025" (!) thick in order to get the wrench on the nut. With the magneto on, that's going to be a rough one.

A difference in thickness of the barrel base flange at the tappet block bore is still very much "a thing" and has resulted in the needed modification of the tappet blocks and pushrod tubes in order to get the proper crush on the seals. If you've got some good measuring tools, the tappet block setting tool, a lathe, a tiny adjustable reamer for the tappet blocks, and a boatload of pushrod tube seals, then it only takes a few hours. Easy peasy, right?

The barrels are .018" taller than a stock 650. Don't know if the pistons are a corresponding amount taller, or if the compression ratio is something that falls where it falls based on various parts.

I've timed the cams' centers to 98 inlet and 102.5 exhaust (supposedly for less ethanol ping and more mid range torque -- it's a big bore 750, right?) and going to give it a go.



Your results may vary.

If there's more interest in this dumb project of mine, I'll move follow ups (or this could be moved by an admin) to the Triton Category.

If there’s interest ?!

Yer shitin’ us right ?

Get the Triton build thread goin’ already…

Fast Eddie said:

As an aside, are you sure it’s (only) the tappet block holes?

It could be the cam lobes.

Or that the cam as a whole needs moving and shimming.

Or a combination of the above.

Click to expand...

That is also what I think. If the cam is too far in one direction, it would appear as though the tappet block is in the wrong place. If a new cylinder base gasket exactly fits both the crankcase and the cylinder, the tappet block is in the right place. It might be the cam needs to be shimmed towards the drive side of the cases, or a shim removed from the timing side. The cam bush might be a bodgie.

Thanks for that lengthy post and follow up.

Crikey , Seeing you mentioned TRITON , AND its a Pre Unit . Or Non Unit . Without the harsh Unitary Vibration & lack of accessability , amougst other things ,
We will trow this picture on .



Thats what happens if someone drives a 70 Commando into a mercedes . and you chop it up. And weld it .
68 Tri swing arm , so the frames narrower, lighter & more comfortable . And handles unsealed roads good. On triangular tyres . Round ones .
68 tri shocks . Short roadholders . Comm Fr. Brake . Non Q.D. Tri rear axle in Conical hub rear .Progressive rate spings. Chromed ones even .
INCIDENTLY , there was a 25T Tri monoplex engine sprocket . tho the Duplex Chain unit primary drops in the Swing Arm P U chaincases .
Then ya gotta have the rear sprocket changeable if ya want tall gearing . your wasting your time if its NOT 100 mph plus, n 3rd .

incidently , the other picture of this , on its side & imonisarse ,

you can see the Megas , with the perorated baffles held in with three rivets , if theyre replaced by three pk screws , ifhe hadem in .
These on 1 3/4 56 Tri Pipes or whatever cut to 27 1/2 or whatever ( The Boyer Tooned Length ) will gettagood P U up past 8.000 .
with 1 1/8 or better ports . 1 5/32 carbs . or better .


the crank on the left is crankier , as its lighter . So wooses cant handle it . even if itis a TT and Thruxton crank . they prefer the dowdy heavy slow reving not quite there crank .
Any idiot knows you lighten the flywheel in anything . this is about the same . If your going to get on it itll get going if youve got it . as long as you can ride properly .

the 72 % ?? Balance Factors likely better too . DONT have ANY PAINT , ANYWHERE , between bits bolted up in the engine cradle / chassis .
Use the fine thread H T Cycle Thread suckers and wind em down real firm . After its all settled in . Or nothing'll work .

Some imbaciles dont fit a good head steady into manx Norvins & suchlike . Braking Torsion eventusally snaps the frame front off . Or an endo . or both .
Having a well engineered light adequate well secured head steady is a A1 priority .
AND ,
Id tilt the cylinder FORWARD , so the primary low run is flat . So the pipes dont drag .AND the Vertical Vibrations ARNT vertical . Steve Lancefield patented this . Now you know .

Youd see thatsilver things like that , if it wernt at full travel on a beer crate . as they still hadem backin 81 . Boutas fastas a good shortstroke mank , that buta lotlighter .

P.S.

We'd like more bl**dy pictures . Of everything . all the time . you can call the machine ' Unfit for youse ' or everyone will wanna ride .

AND


whaderya pistons weigh / compared to std hepolite 650 40 over 9.5 : 1 ones !

p.s. they run real good on Castor Monograde , & you want a BIG oil tank . alluminum even ( home made ? ) fibregass is a insulator so dosnt cool oil well .

Do unit construction Triumphs handle better than Tritons ? When you have lot's of go you need a bike which does not easily exceed it's handling limit. If you ride any bike fast enough, it will usually mis-handle. It is not a problem if you know what you are doing. But when you are on full lean at high speed, it pays to be SMOOTH. You can have the fastest motor and still lose. All you have to do is chirp the front tyre. The bike's weight balance often determines how fast you can ride it. It is sometimes sensible to be a woose.
When I think about my early racing career, I feel sick. I learned a lot, but I still feel the pain. The last time I raced I was up the front and it was easy. I am now 80 and I would gladly race tomorrow,

Do unit construction Triumphs handle better than Tritons

Depends who's Triton & who's unit triumph .

The Inter & Manx Chassis is a notch or two bettern a old Dommie . You see Norton Chassis pictures with ten foot ( well , overlength anyway ) front ends on em .

Id think these ' mold unreliable ' Triumphs , half never went right as they were never tuned , maintained , or run in right , !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
The average road test had maybe ( if they were lucky ) 1000 miles on it. USUALLY LESS .

My theory of not past 1/4 throttle till 500 miles & not held wfo untill 2000 , and even then judiciously , so its loosened of & bedded in ' PROPER ' at 4 or 5 Thousand miles ,
FOR BEST PERFORMANCE
obviously wasnt adheared to .

Somebodys just hit zero in my estimation . As Sliperry Sam was torched , it is NON EXISTANT . a crime worse than murder . as no ' justifieable Homocide ' involved THERE ! .

So this thing HAS NOT thousands of racing miles under its belt . It OBVIOUSLY set up like a piece of shit . So the VIDEO IS GROSSLY MISSLEADING . Thanks CARL .


Right , where were we !

Oranges & Apples !!!!!!!!!!!!!!

HANDLE WHAT .

A fit as phuck pharm boy , did 50 miles in 27 minutes on a stock 72 Trident . Half on gravel . TIMED . " David Brown 111.11 " a Featherbed wouldntve , not on the dirt .
I dont think theres ever been as versatile a machine as the ' Triumph twin ' . and never will be .

A ' Triton ' would likely be a useless dirt tracker . But the TT on a Road track'd be fine . If it had brakes .

Basically a road race spec Bonnie needs a front brake , alloy rims , another gear would help ( now you can get SIX SPEDD GEARS ) and weight shedding .
Ray Knight was building a 74 750 Truxton back then . Never saw the later articles on it . but a chrome moly chassis ( Trackmaster ) would be lighter & stiffer .

As NORTON sold only MANXes , not ENGINES to the formular 500 motor racing crowd , it was once in olde blighty not hard , if not inexpensive , to obtain
a NEW MANX ROLLING CHASSIS , which wouldnt make a bad Triton ( unless that is a fallacy ) .WHEREAAS the Untidy States was more the place to find
Top Line Triumph Tooning & Chassis Stuff . And then theres the Rider . Just cause the same rider rode BOTH , dosnt mean He isnt more suited to one than the other .
So We'll have to get Jay Springsteen as the Test Rider .




SO , The UNIT TRIUMPH handles a LOT BETTER than the NORTON ! if youre not carefull !



But The COMMANDO is significantly FASTER than these new Rocket Threes , even with Turbo's !!!



So new triumphs have NONE of the credability of the REAL ONES . against all comers . sadly . always fell deflated when I realise what I see ist a real Bonnie .

In fact , a real triumph would be OUTCORNERING the Whizz Bangs , and a real good one'd out accelerate em too . But it might not be quite stock .
But nothing ever is , at the front .



So theres skake on it . Halfe arssed Jap engineering from the U K . just look at the twins frame . looks like a back yard hirohito job from ww ii .
Whereas at least the new Norton Frames look like engineers and top fitters mightve had something to do with it .



Some people are so despearte , theyll try anything .

However ,
If you want The Best Bike ,

Youve still got to build ( assemble ) it yourself !!

Raced that Triton Against 1100 Katanas and in 500 open , Pukekohe .

Held of the suzookis a few laps , and stoped for half an hour at the hairpin to let the rest through . TZ 350s on the short circuit mightve come close if theyed left there fairings off , weight / restriction .
on the ' Club ' short circuit .
Obviously I was a much better rider , as it couldntve been the bike !


Actually the Katans were like the queen mary coming up beside you . Then they decided to stop for the corner . But you were only half way down the straight at that stage of the game .
AND you got on the throttle half an hour earlier than them too . untill theyed warmed themselves up . whereas I shoulda bin running 10 thou valve clearance not 4 & 6 , and was a
bit concerned things might snap , as the frame was home cobbled and a prototype not a finished Pro Welded job . woulda doneanother in 1 1/4 Tube manrel bent . But got sat on .

Like to see oneoffthese new triumphs FIRST over widowmaker too . or try it at all . ? Youd think these old ones being so unreliable it wouldve stopped half way up for a rest .

you can see thats ' Pretty stock ' . . Just the right combo & carefull assembly .

The crank on the left is a Saint crank. They are cheap because nobody wants them.. The Saint was the unit construction Tiger 110. They were slower than the pre-unit Tiger 110 because of the lighter crank. They were designed for police use. The heavy crank gives better performance in the 650 motor. My mate bought a couple of those light cranks by mistake. So if you've got a one-piece heavy crank to swap, he might be interested.
Have you weighed a billet Nourish crank ? We bought one - it is a monster. The bike it ended up in won many historic championships. We used Puma crankcases.
The mass of the crank affects throttle response, but if you have the heavy crank spinning high and race-change up through a close rato gearbox, they are beautiful. Some guys don't know how to use the gearbox to go faster. All you do is peak the motor out, then back-off very slightly to take the pressure off the gears, then press the lever. You should only drop about 1500 revs at each up-change. Picking that up is never a problem. My problem with the Seeley 850 is to avoid over-revving. I always try to change up just before 7000 RPM, but usually see 7,500 on the counter.