P/S, the reason the link pipe was fitted in the first place, was due to the extreme restriction of gasses in trying to make less noise. So by joining both down pipes together, they inceased the volume or space to allow a little more room for expansion. Without that mod, the pore motor would not be able to breath, or exhale. Also try fitting thous stifeling silencers on strate through down pipes, & your bike just will not run properly! The Triumph engine runs best, with strate throughs, or to keep on the right side of the law, use the old reverse cone 'aloy' megaphones. Your Triumph will love you for it.🇬🇧👌
Nice one John, I too noticed the difference in sound after doing mine and it definitely runs better now its done. What I have noticed that you might want to check after a long ride is the colour of the plugs, mine started running a little richer and fouled a couple of plugs, I put B5ES Plugs in now and all is OK, I read on some spark plug guru page that you need to go up a heat range using ethanol petrol and as a B6ES is equivalent to a Champion N5C I went for the B5ES.
A really odd problem, with a simple solution that has cured it, great. With the original large restrictive silencers the balance pipe helps breathing, and quietens the bike down as each cylinder breaths through two silencers. So is your bike a little louder with the balance pipe blocked up and pea shooters fitted, compared to an unblocked pipe with the pea shooter silencers? Not that the pea shooters offer much in the way of silencing anyway, they just sound great. The balance pipe also helps prevent the push in type exhaust pipes from popping out of the cylinder head. I have seen some replacement exhaust pipes without the balance pipe that still have a tie bar in its place, to help keep the push in pipes in the head. I've had three Triumph T140's over the years, and really like them. I had a very low mileage 1979 T140 in 1983, factory fitted with Lucas Rita electronic ignition and Amal MK2 carbs, plus those large restrictive original silencers. The MK2 Amals worked without trouble, always with a reliable steady tick over, but with just a slight hesitation when quickly opened up from a standstill for a quick getaway. So I bought and fitted a new pair of those Norton pea shooters, made by Campbells, and the original exhaust pipes still had the balance pipe fitted, and no re jetting of the carbs. The bike ran really well, with better throttle response and a livelier performance, plus a glorious roar when wound up......happy memories. Anyway, it just shows how individual examples of the same bike, with the same setup, can still behave so differently. Although mine was a very low mileage bike, and petrol was a bit different way back in 1983.
when I had my T140E with Toga peashooters, I changed jets and plugs and carb slides to ones with a different cut away. this was over 30 years ago so can't remember any details like numbers etc.
I actually machined down two short pieces of roundstock and drove them instead into the crossover ends on the exhaust pipes- same deal really but I didn't want a jagged exhaust path down inside the exhaust pipes. Also fitted some Norton Commando style peashooters which suit the bonny really well don't they?
I have another link pipe I will probably do what you have done blocking each end and yeah I think the peashooters look so much better than the old cigar things
Common misconception is that those silencers are peashooters. They are Norton style reverse cone megas. Peashooters are the older triumph and BSA type silencers with the tail pipe.
I have stated this before on RUclips, 'Balace pipes' screw up the natural flow! You only need to see any race engine, & the pipes always have a very smooth flow.
It looks like the balance pipe was to thick, you have left a little cave of air volume on one side, I wonder if your get decel pop ,interesting vlog man✌☘
Look how much carbon came out when you test fit the slug i wouldve gone full length up to the clamp slots to help stop carbon building up luckily my pipes are straight through no cross pipe mines a 76 tho
So you have that tube that links the carbs blocked off as well as the crossover pipe? It's crazy how much of a difference the exhaust can make. I got a beat up old T140 recently. With the aftermarket mufflers it had on it, the bike was really loud and popping when I'd let off the gas no matter how I tuned the carbs. I put some stock style mufflers on it and it's a whole different bike. It sounds way better and there's no popping at all, not even durning deceleration. It's so much nicer to ride now. I have bikes that pop a little on decal, but not like this T140 was doing. My neighbors were not fans.
Got one! … but that exhaust ‘push fit to head’ arrangement (as if Meriden could do tolerances) with the little fin collar for ( it would seem) ornamental function only seems like crap engineering! My T140 is very pretty .. but i am reluctantly going to chop it in for a Honda ( appreciate reliability). will keep the BMW! No surprise to me we lost the market.
Was wondering what your initial issue was with the bike?. I purchased a 1973 OIF T120 with a T140 top end. Lovely bike and runs perfectly with a bit of throttle, but sounds odd on (uneven) tick over and tends to run rough at low speed. Throttle open and it sounds and runs superb, not so at lower speed. Carbs have been checked, ignition replaced with electronic, timing checked, all spot on. Currently running “ cigar” silencers and looking to replace with pea shooters. Would really appreciate any suggestions with regards to your experience with your own bike. Cheers, Karl.
Hi Karl, I had the cigar silencers and the Dunstall replicas on the Triumph and the bike run fine, but as soon as I put the peashooters on the bike would stumble on acceleration with a huge dead spot coming off idle. I tried countless carb setups including changing everything, I even went out and bought another set of carbs thinking it was a carb issue. The tickover was ok but not great and the plugs would either been way too lean or way to rich, I just couldn't get the bike to run properly and at one point was thinking of just selling it and moving on, at low speeds or say plodding along at 30mph the bike would miss fire every now n then, pulling away from turnings was a nightmare as the bike had that dead spot which was most annoying . I blocked up the balance pipe, put the carbs back to standard EPA settings and had no problems at all, the bike runs as it should and like it just came off the production line.
Thanks for the reply and the comments, interesting stuff and something that I will certainly look into. It’s an annoying problem as I’m sure it’s something and nothing. Still starts first kick although rough (ish) tick over and slight splutter below 30mph, above that and it runs like a watch .
If you are running the original T120 mk 1 Concentrics on your T140 top end, it may be worth checking the main jet sizes, throttle cutaways and needle positions, as there are small differences between the 650 and 750 (T140V with cigar silencers should have 190 main jets, no 3 cutaway slide and needle in lowest position as standard - I find these settings work on mine with peashooters as well). I would advise cleaning out the pilot jets as well, as these can affect low speed/throttle running. If the carb slides are out of sync, that can affect initial pickup from idle. There is an easy low-tech way to check throttle sync - back off the main throttle cable adjuster and both throttle stop screws so that both slides are fully bottomed out, remove the carb to airbox connectors and insert a piece of stiff wire about 3 inches long under each slide. When you open the throttle, you can see if both wires start to move at the same time and make adjustments to the individual cable adjusters as necessary. Once you have the cables synchronised, you can use the same method to synchronise the throttle stop screws.
Had 7 bikes over last 30 years always had those pipes on never had a problem nor any my mates I reckon its to do your crank it's certainly not pipe though your quick fix nay seem to initially cover this it won't your heading completely fucked engine I'd strip it down quickly
If it was the crank, how on earth would changing the exhaust system alter the workings of a crank? There is nothing wrong with the engine whatsoever, I've already had it apart putting new parts back on and my fix is not a "quick fix" you can purchase single header pipes for these bikes anywhere, are you suggesting buying single header pipes is a "quick fix" to? It is plain to see from any mechanic that the flow of the exhaust was too great using the balance pipe and straight through silencers, by adding the plugged up pipe I cut the exhaust by half from each cylinder making the bike run great like it does with the original cigar silencers, crank my arse.
@@OldBiker That is interesting. My other question is why do manufacturers go to the trouble of adding a balance pipe then it is detrimental to performance?
@@TonyLing The Original silencers needed the balance pipe, aftermarket silencers basically have no baffles so there is no air restriction, even less with a balance pipe
I did try that but the tick over gets erratic, the only time the balance pipe is not used is when I sync the carbs up, if you get the bike running ok and you think its all done, put the vacuum gauges on and see what the carb sync is like, you'll be surprised how much more you need to do to get it running properly! Leave it connected as it evens the carbs up, especially if one carb is more worn than the other.
@@OldBiker ok i tried vacum gauges once but the needles were all over the place wasnt sure weather to trust this method,getting the same vacum on both at say 2500 was unachievable ?
@@garethlipyeart6520 I tried vacuum gauges forty years ago on my friend's 73 Bonneville, when the slides are tight, getting vacuum isn't too hard, but once they're worn loose, not much use. I just did the same job on my 78 Bonnie, and it cleaned up the low end, and idle nicely, made running up nice and smooth. My current bike has new carbs, nice and snug, I don't really know how to act right now. I had a 64 TR6R forty years ago, and it's hard to even come close to matching the smoothness and running of a single carb. The do run substantially stronger with two though.
P/S, the reason the link pipe was fitted in the first place, was due to the extreme restriction of gasses in trying to make less noise. So by joining both down pipes together, they inceased the volume or space to allow a little more room for expansion. Without that mod, the pore motor would not be able to breath, or exhale. Also try fitting thous stifeling silencers on strate through down pipes, & your bike just will not run properly!
The Triumph engine runs best, with strate throughs, or to keep on the right side of the law, use the old reverse cone 'aloy' megaphones. Your Triumph will love you for it.🇬🇧👌
A touch of the Alan Millyard engineering in this vid, good job
Having just watched you, I just did this to my own Bonnie, and she sounds great, runs better, thanks!
Nice one John, I too noticed the difference in sound after doing mine and it definitely runs better now its done. What I have noticed that you might want to check after a long ride is the colour of the plugs, mine started running a little richer and fouled a couple of plugs, I put B5ES Plugs in now and all is OK,
I read on some spark plug guru page that you need to go up a heat range using ethanol petrol and as a B6ES is equivalent to a Champion N5C I went for the B5ES.
Clever mod! I managed to source new pipes for a bargain but probably would have done this had I known. 👍🏻
Top tips mate, going to do that with my T140
A really odd problem, with a simple solution that has cured it, great.
With the original large restrictive silencers the balance pipe helps breathing, and quietens the bike down as each cylinder breaths through two silencers. So is your bike a little louder with the balance pipe blocked up and pea shooters fitted, compared to an unblocked pipe with the pea shooter silencers?
Not that the pea shooters offer much in the way of silencing anyway, they just sound great.
The balance pipe also helps prevent the push in type exhaust pipes from popping out of the cylinder head. I have seen some replacement exhaust pipes without the balance pipe that still have a tie bar in its place, to help keep the push in pipes in the head.
I've had three Triumph T140's over the years, and really like them. I had a very low mileage 1979 T140 in 1983, factory fitted with Lucas Rita electronic ignition and Amal MK2 carbs, plus those large restrictive original silencers. The MK2 Amals worked without trouble, always with a reliable steady tick over, but with just a slight hesitation when quickly opened up from a standstill for a quick getaway.
So I bought and fitted a new pair of those Norton pea shooters, made by Campbells, and the original exhaust pipes still had the balance pipe fitted, and no re jetting of the carbs. The bike ran really well, with better throttle response and a livelier performance, plus a glorious roar when wound up......happy memories.
Anyway, it just shows how individual examples of the same bike, with the same setup, can still behave so differently. Although mine was a very low mileage bike, and petrol was a bit different way back in 1983.
Clever fix and impressive self discipline in postponing test ride! 😅
when I had my T140E with Toga peashooters, I changed jets and plugs and carb slides to ones with a different cut away. this was over 30 years ago so can't remember any details like numbers etc.
I actually machined down two short pieces of roundstock and drove them instead into the crossover ends on the exhaust pipes- same deal really but I didn't want a jagged exhaust path down inside the exhaust pipes. Also fitted some Norton Commando style peashooters which suit the bonny really well don't they?
I have another link pipe I will probably do what you have done blocking each end and yeah I think the peashooters look so much better than the old cigar things
Common misconception is that those silencers are peashooters. They are Norton style reverse cone megas. Peashooters are the older triumph and BSA type silencers with the tail pipe.
I have stated this before on RUclips, 'Balace pipes' screw up the natural flow! You only need to see any race engine, & the pipes always have a very smooth flow.
It looks like the balance pipe was to thick, you have left a little cave of air volume on one side, I wonder if your get decel pop ,interesting vlog man✌☘
Look how much carbon came out when you test fit the slug i wouldve gone full length up to the clamp slots to help stop carbon building up luckily my pipes are straight through no cross pipe mines a 76 tho
So you have that tube that links the carbs blocked off as well as the crossover pipe?
It's crazy how much of a difference the exhaust can make. I got a beat up old T140 recently. With the aftermarket mufflers it had on it, the bike was really loud and popping when I'd let off the gas no matter how I tuned the carbs. I put some stock style mufflers on it and it's a whole different bike. It sounds way better and there's no popping at all, not even durning deceleration. It's so much nicer to ride now. I have bikes that pop a little on decal, but not like this T140 was doing. My neighbors were not fans.
Great mod! I would of placed 2 plugs , one on each side with them cut at an agle to match the main pipe. You might get a bit better flow??
Got one! … but that exhaust ‘push fit to head’ arrangement (as if Meriden could do tolerances) with the little fin collar for ( it would seem) ornamental function only seems like crap engineering! My T140 is very pretty .. but i am reluctantly going to chop it in for a Honda ( appreciate reliability). will keep the BMW! No surprise to me we lost the market.
People don't understand the function of the balance pipe.
Was wondering what your initial issue was with the bike?.
I purchased a 1973 OIF T120 with a T140 top end. Lovely bike and runs perfectly with a bit of throttle, but sounds odd on (uneven) tick over and tends to run rough at low speed. Throttle open and it sounds and runs superb, not so at lower speed.
Carbs have been checked, ignition replaced with electronic, timing checked, all spot on.
Currently running “ cigar” silencers and looking to replace with pea shooters.
Would really appreciate any suggestions with regards to your experience with your own bike.
Cheers, Karl.
Hi Karl, I had the cigar silencers and the Dunstall replicas on the Triumph and the bike run fine, but as soon as I put the peashooters on the bike would stumble on acceleration with a huge dead spot coming off idle. I tried countless carb setups including changing everything, I even went out and bought another set of carbs thinking it was a carb issue.
The tickover was ok but not great and the plugs would either been way too lean or way to rich, I just couldn't get the bike to run properly and at one point was thinking of just selling it and moving on, at low speeds or say plodding along at 30mph the bike would miss fire every now n then, pulling away from turnings was a nightmare as the bike had that dead spot which was most annoying .
I blocked up the balance pipe, put the carbs back to standard EPA settings and had no problems at all, the bike runs as it should and like it just came off the production line.
Thanks for the reply and the comments, interesting stuff and something that I will certainly look into.
It’s an annoying problem as I’m sure it’s something and nothing. Still starts first kick although rough (ish) tick over and slight splutter below 30mph, above that and it runs like a watch .
If you are running the original T120 mk 1 Concentrics on your T140 top end, it may be worth checking the main jet sizes, throttle cutaways and needle positions, as there are small differences between the 650 and 750 (T140V with cigar silencers should have 190 main jets, no 3 cutaway slide and needle in lowest position as standard - I find these settings work on mine with peashooters as well). I would advise cleaning out the pilot jets as well, as these can affect low speed/throttle running. If the carb slides are out of sync, that can affect initial pickup from idle. There is an easy low-tech way to check throttle sync - back off the main throttle cable adjuster and both throttle stop screws so that both slides are fully bottomed out, remove the carb to airbox connectors and insert a piece of stiff wire about 3 inches long under each slide. When you open the throttle, you can see if both wires start to move at the same time and make adjustments to the individual cable adjusters as necessary. Once you have the cables synchronised, you can use the same method to synchronise the throttle stop screws.
@@OldBiker didnt u say you had a dough coil ?
Had 7 bikes over last 30 years always had those pipes on never had a problem nor any my mates I reckon its to do your crank it's certainly not pipe though your quick fix nay seem to initially cover this it won't your heading completely fucked engine I'd strip it down quickly
If it was the crank, how on earth would changing the exhaust system alter the workings of a crank? There is nothing wrong with the engine whatsoever, I've already had it apart putting new parts back on and my fix is not a "quick fix" you can purchase single header pipes for these bikes anywhere, are you suggesting buying single header pipes is a "quick fix" to?
It is plain to see from any mechanic that the flow of the exhaust was too great using the balance pipe and straight through silencers, by adding the plugged up pipe I cut the exhaust by half from each cylinder making the bike run great like it does with the original cigar silencers, crank my arse.
Why do you need back pressure on a four stroke?
www.klarius.eu/understanding-back-pressure/
@@OldBiker That is interesting. My other question is why do manufacturers go to the trouble of adding a balance pipe then it is detrimental to performance?
@@TonyLing The Original silencers needed the balance pipe, aftermarket silencers basically have no baffles so there is no air restriction, even less with a balance pipe
@@OldBiker OK, thanks. I'm looking at getting a SS exhaust for my Guzzi V50
the rubber balance pipe underneath have u blocked that off was wondering weather to do that on my t140d
I did try that but the tick over gets erratic, the only time the balance pipe is not used is when I sync the carbs up, if you get the bike running ok and you think its all done, put the vacuum gauges on and see what the carb sync is like, you'll be surprised how much more you need to do to get it running properly! Leave it connected as it evens the carbs up, especially if one carb is more worn than the other.
@@OldBiker ok i tried vacum gauges once but the needles were all over the place wasnt sure weather to trust this method,getting the same vacum on both at say 2500 was unachievable ?
@@garethlipyeart6520 I tried vacuum gauges forty years ago on my friend's 73 Bonneville, when the slides are tight, getting vacuum isn't too hard, but once they're worn loose, not much use. I just did the same job on my 78 Bonnie, and it cleaned up the low end, and idle nicely, made running up nice and smooth. My current bike has new carbs, nice and snug, I don't really know how to act right now. I had a 64 TR6R forty years ago, and it's hard to even come close to matching the smoothness and running of a single carb. The do run substantially stronger with two though.
The needles will bounce around if you don't have valve just below the gauges
why do this?
I done it to increase the back pressure so that each pipe acts independently, it also saves me buying two new seperate header pipes.
Norton silencers are for Nortons.
My mate has them on his Suzuki, good job on Norton for making them a universal fit huh
@@OldBiker Sacrelidge.