T120V 5 Speed - Indexing, False Neutrals Etc

[speedrattle]

by the way, in america these covers are inexpensive. dunno about over on your side.

https://www.ebay.com/sch/i.html?_fr....l1313&_nkw=triumph+650+timing+cover&_sacat=0
i would buy another and save the split one for somebody in another 100 years who doesn't have that option.

 

[sikatri]

by the way, in america these covers are inexpensive. dunno about over on your side.

https://www.ebay.com/sch/i.html?_fr....l1313&_nkw=triumph+650+timing+cover&_sacat=0
i would buy another and save the split one for somebody in another 100 years who doesn't have that option.

Just me, but I’d repair it just in case. Perhaps in a hundred years someone would lift a glass to me! LoL.

 

[Woollybandit]

The way things are going it will be illegal to own/run an internal combustion engine in 100 years.
This side of the Atlantic the foolish politicians say ICE will be illegal to build by 2030!
Either
(a) they are deluded beyond belief - no way that many vehicles will be bought or even bake to be charged so soon
(b) they intend to deny fuel engines to the general public
(c) that is the start of civil war

Off topic?

 

[grandpaul]

The way things are going it will be illegal to own/run an internal combustion engine in 100 years.
This side of the Atlantic the foolish politicians say ICE will be illegal to build by 2030!
Either
(a) they are deluded beyond belief - no way that many vehicles will be bought or even bake to be charged so soon
(b) they intend to deny fuel engines to the general public
(c) that is the start of civil war

Off topic?

SLIGHTLY off-topic, as it involves the fate of motorcycles.

It has been studied and confirmed there is NO WAY to have the electrical generation capacity required to CHARGE all of the world's EVs if the entire planet converted (as in, eliminate ICE engines). Not in 100 years, not even close.

Now, IF, TOMORROW a new discovery is made that will revolutionize electrical generation, it would still take DECADES to ramp up capacity (study the evolution of today's EVs and the evolution of the charging facilities. As it exists, I believe the available capacity represents SINGLE-DIGIT percentage of the world's vehicles.

 

[Rudie]

New cover arrived today and new switch hand threads in 3/4 of the way then nips up almost like it bottoms out.
The new primary casing is 70-7318 (broken one is 70-8797) with straight cut thread to suit 60-3719 switch. It has the swage milled for the 4 valve pump but fits perfectly.
I've found an old switch which runs into the hole to the washer so maybe I'll wet and dry the peaks of the new switch threads and see how it goes in - the old switch was 9.8mm OD whilst the new is 10.1mm ….. a bit tight.

No, this is suspicious ...

The new primary casing is 70-7318 (broken one is 70-8797)

These are numbers actually cast on the covers? If so, it is a mildly complex subject ...

Part numbers printed in parts books are for 'finished' parts, that can be assembled to make a working motorcycle.

Triumph (and parent BSA) also used 'part numbers' to track work in progress within the factories. A number cast on a part (as opposed being stamped into it) was the 'part number' of an original casting, before machining and/or other finishing. In the case of something like the timing cover, that had to have the hole for the crank end and seals machined, the oilway end tapped either 3/8"-26 (pre 69) or 1/8"NPS (69 on), etc., the cast part number is not normally the same as the 'finished' part number.

However, 70-8797 is the part number printed in 68 650 parts books. 68 was threaded for a 26 tpi 3/8" Cycle bolt, not a larger-diameter and 27 tpi 1/8"NPS oil pressure switch ... So, because it is easy to find 70-8797 with Google:-

. either this is a pattern cover (that the pattern part maker cast "70-8797" on for potential customers who would be suspicious of the original Triumph cast part number because they could not find it with an internet search);

. or the cover was broken by an idiot PO trying to force in an oil pressure switch.

70-7318 is in between the 'finished' part numbers for 67 ((70-)E4567) and 68. The casting might have been machined to make a 'finished' E9246, as fitted 69 on and to your bike's engine originally, but it would be wise to check more carefully?

found an old switch which runs into the hole to the washer so maybe I'll wet and dry the peaks of the new switch threads
the old switch was 9.8mm OD whilst the new is 10.1mm ….. a bit tight.

No!

If you "don’t want to push my luck with the new cover", then know what you are doing! If you do not know what you are doing, Ask?

If you know "the old switch was 9.8mm OD whilst the new is 10.1mm" you are clearly measuring with something more accurate than an ordinary ruler.

You also obviously have an internet connected computer in front of you. So why do you not use it to look up the correct diameter of the switch you are supposed to be fitting?

"10.1mm" is 0.398"; I have posted already that the major diameter of 1/8"NPS is 0.405". 0.398" should not be "a bit tight" inside 0.405". Maybe read the beginning of my post #14 again ...

Otoh, "9.8 mm" is 0.386". By possibly an amazing near-coincidence, 1/8"BSP's major diameter is 0.383" ... and 1/8"BSP pressure switches are very common in the UK ...

found an old switch which runs into the hole to the washer
old switch was 9.8mm OD

If it is 1/8"BSP, it will be 28 tpi; this is obviously very close to both 27 tpi and 26 tpi; one of the symptoms of two tpi that similar but not the same is, "hand threads in [part] of the way then nips up almost like it bottoms out" ...

In addition to your calipers or micrometer, do you have 26, 27 and 28 tpi thread gauges? If you do, maybe break them out and clarify exactly what you have? If not, maybe order them online before proceeding much further?

 

[speedrattle]

rudie's suggestions as to actually measuring what you are working with here are very pertinent.

most any of the oil pressure switches will almost fit in almost any cover. then if you crank down on the wrong switch to make it tight or to stop an oil seep the timing cover will crack.

all these motors are pushing 30 to 50 years or better. the timing cover on your machine may or may not be the one that the factory installed. in fact, it may have been replaced because the PO cracked it trying to tighten the wrong oil pressure switch.

measure the threads. see whether you have a straight or tapered hole. be attentive as you install the switch.

 

[sikatri]

I’d do exactly what @Rudie noted above. You have to know exactly what the thread is in the cover and the device being threaded. There is no such thing as close.

 

[grandpaul]

You have to know exactly what the thread is in the cover and the device being threaded. There is no such thing as close.

Actually, the PROBLEM is, that there ARE things that are "close" but INCORRECT! Here you see a broken cover as a result of "close"...

(I know, nit-picking)

 

[sikatri]

Actually, the PROBLEM is, that there ARE things that are "close" but INCORRECT! Here you see a broken cover as a result of "close"...

(I know, nit-picking)

Nit-pick away! LoL. I know what you mean. I replaced my carburetor screws and the set I received had one wrong threaded screw. Close. I caught it trying to screw it in and it felt different. I stopped and contacted the vendor. They quickly sent me a few more and apologized. If I had been inattentive I could have stripped the threads in the carburetor. Always should check. I should have checked the full set before starting.

 

[Woollybandit]

Ok, just back from the workshop.
The old dead switch that I found in my cabinet and goes straight into the new cover is definitely straight 9.8mm/0.39” OD measured with vernier and 27tpi
The one that came with the engine and 'nips up' 3/4 of the way in is also 27tpi measured using a thread gauge but is tapered 10.2-8.8mm. So …. glad I didn’t force it into my replacement cover! Just pinkies. Phew!
Old 70-8797 casing is (was) straight threaded but had that tapered switch wedged in, which is why it leaked. Will order new straight 3/8” now.
The 70-7318 is a exact match for the old one but is chromed and has space for a 4 valve pump, I believe is a LF Harris modern product. It will suffice until the 70-8797 alloy case comes from South Carolina later in the month. It doesn’t look too bad anyway
Btw, both cases have their numbers cast into the back as shown in photo.

Anyhow, I can’t express how much I appreciate your help here and sure glad I registered with this forum BEFORE reaching for my longest ring spanner!
I might have in ignorance sent another case to the scrapyard without your intervention. Side by side you can clearly see the taper, but not in isolation. Thanks Rudie.

 

[Woollybandit]

Afterthought…… does anybody have experience of external pressure gauge fed from this port in place of the switch?
I have one on my FXDB and appreciate what’s really going on over revs and temperatures.

 

[Greyfell]

SLIGHTLY off-topic, as it involves the fate of motorcycles.

It has been studied and confirmed there is NO WAY to have the electrical generation capacity required to CHARGE all of the world's EVs if the entire planet converted (as in, eliminate ICE engines). Not in 100 years, not even close.

Now, IF, TOMORROW a new discovery is made that will revolutionize electrical generation, it would still take DECADES to ramp up capacity (study the evolution of today's EVs and the evolution of the charging facilities. As it exists, I believe the available capacity represents SINGLE-DIGIT percentage of the world's vehicles.

True. The only known existing technology capable of generating the required power is the hated nuclear power plant, a lot of them. Next, and maybe bigger, challenge is getting that power to the user, in the form those users can use. In the USA, nearly all neighborhoods are getting single-phase power, and the transmission transformers and cables were put in place for a certain design power usage. To change over to supporting just mostly electric vehicles (a ton more amperage/kilowatts) would require (in order)
1 revamping the transmission cables to 3-phase and much heavier-duty
2 adding or replacing transformers that are much larger (and preferably buried)
3 upgrading the neighborhoods for greater power usage (currently rated for about 10,000 amps)
4 upgrading homes for greater power usage (currently most modern homes are rated for 100 amps)

Making those improvements to the power grid will be insanely expensive and time consuming!

Putting an EV in your garage, could overload your house, but of course you charge the EV at night, right? But, here in California, we're told not to run air conditioner or major appliances between the peak hours 6PM and 9PM (which is also billed at a higher usage rate). But, if many people have EV's and charge during the night, Those nights will become the NEW peak usage times, and billed at the higher rate; so are you saving money, now?

We can't just think of how an EV affects our own lives; we have to think how they are going to affect our world, the bigger picture.

 

[Rudie]

The old dead switch that I found in my cabinet and goes straight into the new cover is definitely straight 9.8mm/0.39” OD measured with vernier and 27tpi
The one that came with the engine and 'nips up' 3/4 of the way in is also 27tpi measured using a thread gauge but is tapered 10.2-8.8mm.

If a "PO" of the T120V of the thread title simply looked in the contemporary parts book and ordered a new oil pressure switch by the listed part number - D2133 - most retailers do not give a damn and happily supply a current production NPT thread switch, although Meriden certainly did not build any twin engines with NPT threads after October 1968 ...

Nevertheless, that in itself would not be a problem if the current switch maker could actually make them accurately consistently

The switch on the right of the photo is current production ...

The switch on the left is either older by the current maker or a Veglia ...

Certainly neither is an original Smiths ...

Thanks Rudie.

Pleased you dodged the bullet.

 

[Woollybandit]

The switch on the right of the photo is current production ...

The switch on the left is either older by the current maker or a Veglia ...

Certainly neither is an original Smiths ...


Pleased you dodged the bullet.

Hehe, with this rebuild it feels like facing a Gatling gun!

 

[Woollybandit]

Just as a wind up to the indexing part of the thread ….. after a few hours of unsuccessful assembly and testing I lost patience and took the bike out into the garden and smashed it to pieces. No I didn’t, that was on my mind at one stage but sense prevailed and I just reassembled the whole bike and went for a ride down the lane.
No false neutrals but only 3rd, 4th & 5th gears. So laid bike on it’s left side in the garage so I di have to drain the gearbox and lifted inner casing so I could swing cam quadrant down two teeth and twenty minutes later had it together with all gears present.
Thanks to all the respondents with help, it did help.

 

[sikatri]

Just as a wind up to the indexing part of the thread ….. after a few hours of unsuccessful assembly and testing I lost patience and took the bike out into the garden and smashed it to pieces. No I didn’t, that was on my mind at one stage but sense prevailed and I just reassembled the whole bike and went for a ride down the lane.
No false neutrals but only 3rd, 4th & 5th gears. So laid bike on it’s left side in the garage so I di have to drain the gearbox and lifted inner casing so I could swing cam quadrant down two teeth and twenty minutes later had it together with all gears present.
Thanks to all the respondents with help, it did help.

Wish you had a few pics, not sure exactly what you did, but congrats!

 

[speedrattle]

interesting. exactly which notch did you use? i have found that when the motor is lying on its left side it is impossible to use the factory procedure for indexing, because the gears fall down their shafts to the left and its hard to lift them to the correct indexing position. you obviously have solved that problem.

 

[Woollybandit]

This was the position prior to lifting the inner case ….. must have been in 3rd gear and I relocated the cam to be 2 teeth further toward the bottom of the picture.
Anyway, it seems to have worked.

 

[amer14]

On my 72 T120TRV I sheared the main shaft on a power down shift, cracked in a typical 45 degree shear fracture right where the splines blend into the round shaft journal, So i was looking at my first experience of transmission remove repair and replace. i was lucky to find a used mainshaft. i followed the work shop manual and i succeeded in the R,R,& R. i think the single most important and helpful technique was using the chain connected routed over countershaft sprocket and around the rear wheel sprocket i also did NOT mount the clutch basket and plates etc. on the main shaft in the primary case. i left the gear box case open so i could diddle with the transmission and shifter plate. I was amazed that i was able to accomplish the R,R & R. If i has access (which i didn't) too a shot peener i would have brought the shaft and peened right where the splines blend into the round shaft journal. hope this is any help.

 

[amer14]

Hi Scottoil, I fear I also broke my main shaft or did some kinda damage in my tranny. T120v 5 speed. I first thought the clutch locked up but have the primary side taken down all the way to the 20 tooth front drive sprocket, chain and rear wheel and sprocket still on. The clutch and everything there looks great. Yes the big nut is off the front sprocket and was tight. The main shaft itself and the drive sprocket seem disjointed only catching each other intermittently when moving rear wheel and chain therefore the front drive sprocket back and forth. So this is where I am. Any advice going forward before I pull the front sprocket and start on the Tranny.