Yet another Triumph Youtube video

Well my mate finally got round to doing a video on my lightly hot-rodded T140V. In fairness I finally got round to finishing the fork rebuild!

Anyhow, check it out here. We're hoping to do a more direct comparison between this bike and my 850 Commando (also filmed this Summer on the same channel) next Spring. They really are very comparable in terms of performance and vibration, not that I've ever had the opportunity to ride them alongside each other, so that will be interesting. Quite different in character though, at least considering they're both '70s brit twins!

I love T140s. Most underrated classic out there I reckon. Of course, many are dogs though, which doesn’t help the ‘brand image’ !

Yours is really nice. Sounds lovely too!

Can you confirm the cams used? I couldn’t find the 510-30‘s listed.

Fast Eddie said:

I love T140s. Most underrated classic out there I reckon. Of course, many are dogs though, which doesn’t help the ‘brand image’ !

Yours is really nice. Sounds lovely too!

Can you confirm the cams used? I couldn’t find the 510-30‘s listed.

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Thanks Nigel,
The 1030 (as it was known before Megacycle renumbered all the Triumph cams) hasn't been made for, I guess, about 15-20years? I got mine secondhand but unused on US ebay around 15 years ago if memory serves (which it generally doesn't!). I think it was still listed in their catalogue when I bought it, which is where I got the "TT" moniker from, not that it means much I guess.
The exact timing/lift figures are on the card in the garage but from a Britbike forum thread I came up with this:-

"Yea the old 1030s were only .010" less lift and 8-9 degrees less duration than the 1060s"

So they are really a half way house between the 510-05 (which I have in my '68 T120) and the hotter 510-65, both of which they still make. I like this cam (not that I've tried the hotter option) because it still plays to the T140 strengths of torque out of the bottom end of the rev range. OK I am pretty light and the bike is really light, but I don't notice any lack of low down oomph compared to the loads of standard T140s I've ridden/owned, and it's probably a more sensible option with the low(ish) compression than a 1065?

Funnily enough I am about to put one of these in an otherwise bog standard T140 I am rebuilding for a mate (bike only 30 engine numbers apart from my mine and still owned by the same guy who rode it when I was riding my dad's!), which should help an otherwise very flat motor, all for £55! Suspect I'll have to dial in this and the standard intake cam though!


Apologies, long reply to a short question!

Thanks!

Looking at the current Megacycle catalogue the 510-65 actually looks good, especially if you substitute the R followers for Standard.

Personally, I’ve always been a fan of the Hyde half race cam and the Spitfire profile cam, often struggling to decide between them!

I have some Hyde half race cams ready for the next time I strip the T140 motor, I think they’ll suit that nicely.

I also have a ‘68 like yours, with the light crank. I LOVE the characteristics of the light crank and want to build the engine to maximise that. So for that I’m intending to fit lightweight forged MAP 9.51 pistons (750cc, with Morgo barrels is the current plan) and Spitfire cams.

All I need now is a round tuit….

Nigel,
I had some Hyde "half race" cams in my T140 before the rebuild about 10 years ago. They wore really badly, though I doubt it was a cam issue, possibly lubrication failure though nothing else suffered?? I'd imagine they're made by Newman or some such? It goes a lot better now but numerous other changes at the same time so hardly a fair comparison.

I DO like the look of those MAP pistons, should make that light '68 go really nicely! We are lucky there is still any kind of aftermarket choice for these old things?

wavey_davey said:

Nigel,
I had some Hyde "half race" cams in my T140 before the rebuild about 10 years ago. They wore really badly, though I doubt it was a cam issue, possibly lubrication failure though nothing else suffered?? I'd imagine they're made by Newman or some such? It goes a lot better now but numerous other changes at the same time so hardly a fair comparison.

I DO like the look of those MAP pistons, should make that light '68 go really nicely! We are lucky there is still any kind of aftermarket choice for these old things?

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Hmmm thats not a good endorsement of the Hyde cams …

Nice Triumph and a very enjoyable video. Thanks for posting.

I must say that I fully agree that the T140 is great fun on the back roads of the UK. The balance between power, handling and soundtrack mean that you can ride it quite hard and yet you rarely end up doing much more that 70mph, and yet it gives me lots of pleasure. Also as I'm starting to age, their lack of weight is also a big plus. The only downsides for me is the knee to kickstart relationship which might start to become a bigger problem as my years increase, and mine does vibrate quite a bit if I start going much above 5,000rpm.

Great bikes.

Don’t worry about vibration at 5,000…. Just rev it to 7,000….!

Fast Eddie said:

Hmmm thats not a good endorsement of the Hyde cams …

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If it's of interest, I fitted a 70-9989 exhaust cam to my TR7 (very similar mods to the bike in the video, except standard barrels and 8.6:1 pistons). I had to take the top end off last year to fit new rings (Tricor Andy sold me a set of bog standard JCC rings in 2012 when I was building the engine, telling me they were Riken rings, and it burned about 1ml of oil per mile ever after). I bought some Goetze rings and they completely cured the oil drinking issue.

Anyway, the engine had done nearly 14000 miles when I took the top off. I was very pleased to find no wear at all to the cam lobes on either camshaft, or to the followers. Just a slight polishing to the surfaces. The kind of wear (lack of) you'd expect in a modern engine or a car engine. So, if that's owt to go by, these exh cams, which I believe are LF Harris items, are good.

Incidentally, the extra torque & power the engine produces with the modified timing and unrestricted exhaust (T140D downpipes & collector box with no silencer) has allowed 21/45 gearing, which it pulls perfectly even in top gear. I used to regularly ride over 2000 mile round trips from Norfolk to the Pyrenees, keeping it at 80-85mph on the autoroutes, without any problems at all. So I slightly disagree with the video about T140s not being well suited for long distance touring. They can be, if built for it.

Tigernut said:

If it's of interest, I fitted a 70-9989 exhaust cam to my TR7 (very similar mods to the bike in the video, except standard barrels and 8.6:1 pistons). I had to take the top end off last year to fit new rings (Tricor Andy sold me a set of bog standard JCC rings in 2012 when I was building the engine, telling me they were Riken rings, and it burned about 1ml of oil per mile ever after). I bought some Goetze rings and they completely cured the oil drinking issue.

Anyway, the engine had done nearly 14000 miles when I took the top off. I was very pleased to find no wear at all to the cam lobes on either camshaft, or to the followers. Just a slight polishing to the surfaces. The kind of wear (lack of) you'd expect in a modern engine or a car engine. So, if that's owt to go by, these exh cams, which I believe are LF Harris items, are good.

Incidentally, the extra torque & power the engine produces with the modified timing and unrestricted exhaust (T140D downpipes & collector box with no silencer) has allowed 21/45 gearing, which it pulls perfectly even in top gear. I used to regularly ride over 2000 mile round trips from Norfolk to the Pyrenees, keeping it at 80-85mph on the autoroutes, without any problems at all. So I slightly disagree with the video about T140s not being well suited for long distance touring. They can be, if built for it.

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Yep I also have to disagree about the t140 not being a long distance bike

I disagree too, but I asked my mate (Mike) who's channel it is, to give his impressions of the various classics in different scenarios (hooning down a lane, rumbling across France etc). I still think the Commando makes a better long distance tool (all relative of course), but there's not much in it, and I'd take either in a heartbeat. Part of Mike's reticence is the seat foam on the bonnie, which I cut down. I have a thing about the later T140vs prior to the "dropside" pattern being a bit thick and ugly compared to the pre '75ish ones. I went too far and you're sitting on the seat pan!
Thanks for your replies, the feedback on the LFH cams is reassuring as one has just arrived for my mate's bike!

Is dyno result of 48 din at crank similar to the factory rating for the T140?

Glen

Triumph factory BHP claims are similar to Nortons IMHO… ie optimistic, but not BS.

I believe the factory quoted 52bhp for the T140. I knew a guy with a single carb Tiger once who was GUTTED to have gotten 38rwhp on the dyno.

I said to him, take off 10% for production tolerances and you’re down to 46.8. take of 5bhp for powertrain losses and you’re at 41.8bhp. And it’s quite likely that the single carb is responsible for all or most of the remaining 3.8 !

There are so many different correction factors, it's difficult to know what's what.
It's always nice to see the actual chart as shown in Davey's video.
Most often you will only be told the big number and it is almost always said to be " RWHP" even though it might be SAE J1349, (15% mechanical added+ weather) , STD (about 4% higher than J1349) and so on.
The DIN test in the video shows the results at rear wheel, gearbox, and engine crank. It would be nice if all tests were done that way.

1 DIN hp is a tiny bit less than 1SAEhp, about 2%

Glen

Sorry, missed all this interesting dyno discussion! The actual chart in the video was before the final mods (port clean up, Megacycle cams) but with the Nikasil barrels, Mikunis I think (long time ago) and possibly partly worn Hyde cams as per my post earlier? My mate Mike who does the videos forgot to put the explanation in the vid.

I recall two Triumph twin dyno results from the UK magazine Motorcycle Mechanics back in the '70s. Their dyno tests were always on a Heenan Froude dyno (run from a chain off the gearbox sprocket) run by a very well respected engineer called Leon Moss. A lot of the other UK dyno facilities "calibrated" their dynos based on his results (Phil Todd of Motodd being one, a Laverda guy).

They got 43 rwhp from a Tiger 750 (single carb) which seems about right to me? The T140E (parallel inlet ports, Mk2 carbs) they tested on the same dyno (crucially) a few years later got a very healthy 49rwhp, but I suspect that was a very good one. They also had to change to colder N3 plugs for that result as the N5s were "fading" at the top end? They recommended N3s for "normal riding though, giving about 47rwhp from memory?
Based on the actual performance of a Tiger vs Bonnie I think the informed opinion was about 3 bhp difference (46rwhp?) on the top end of a good bonnie, and bugger all everywhere else (UK magazines always got the same or nearly the same standing quarter acceleration results from both variants, which relies more on the spread of power rather than just top end).

Based on my (notoriously unreliable) seat of the pants dyno, I'd pitch my T140 in current state at about 5ish bhp above that previously recorded 43 rwhp (on THAT dyno), but that really is a guess? Acceleration slows around 90mph, but the very low weight (around 380lbs with a half tank) and lovely mid range really help it fly up to that point, and with those bars it hardly matters what happens above that speed to be honest! It is as smooth as the Commando at least up to 85, possibly higher but your gripping everything so tight to hang on above that it's difficult to gauge!! A shame Meriden couldn't run to dynamic balancing like Enfield! I'm really looking forward to running them both together for a video in the Spring!