Brian , I'm a Japanese bike guy and once fixed a Bonneville with no idle , just blew air through and it was good . Had no idea where the pilot jet was locared , just was lucky it got cleared ! . 50 years later and I now have an answer ! Btw I today think these were the greatest bikes ever (they had the looks and can be made reliable enough ). My choice , the BSA Lightning 650, 1967.
I love BSA's and have a 250 B25 Starfire and a 500 B50T Victor, always fancied a 650 Firebird (Hornet in the USA) but never had enough cash, now getting a rare bike.
Great fix Brian. Here's another: If you have poor pickup from idle and fussy low speed running as I had on my T140 and particularly my T25T, file the flat part of the bottom of the slide, with radius to match the venturi, to a depth of 1mm (max 1.5mm) creating a sort of mini carb around those two tiny pilot holes. The improvement is dramatic. My T25T 250 Trail Blazer would often cut out pulling away from traffic lights and was hesitant and rough at low speeds. Now it pulls away smoothly and will bimble along at 2500rpm and speed up from there. Impossible before this simple mod. Experiment with old worn slides if you have some. I'm sure it will transform a fussy bike like the twin carb T100!
Hi David, did a tad more fine tuning and balancing on the the Daytona, now running sweet, could never get the B50 right at low revs and idle so bought a new Amal premier which sorted it out. However struggling to get the B25 right and have 4 or 5 spare slides, so will have a go. Regards Brian
Great video Brian, I have just bought my first 1964 triumph and there is lots of oil leaks to fix. You have got a great presentation style, makes it easy to follow you. Thanks heaps.
Hello Brian..great video. I didnt know the mach2 had the remote jet. I was also wondering if it was possible to drill out blanking plug tap, punch out jet and then tap the hole to fit removable jet like on the new premieres?Or is that pathway already too big?
Hi Paul, I did look at fitting a Premier pilot as I have a couple of 2 and 3 band jets in my spares box, however drilling the hole would be quite complicated as the jet runs through 90 degrees where the 4 holes in the side of the jet need to be inline with the cross drilling then at the bottom of the hole you need to have a taper to seat at the bottom end of the jet, plus behind the threads you need to drill a plain section for the jets o ring to seal against to stop air being drawn past the threads. I think it can be done, I think that area is the best place for the fuel pilot restriction just before the chamber where the 2 small holes are drilled at the venturi as the carbs with the removable pilot jet above the float bowl seem to need a choke slide fitted for cold start as the restricted fuel flow has a greater distance to be drawn from the vacuum of the venturi and thats why Amal made the change to the pilot jets position on the Premier. Regards, Brian.
@@TheCADengineer thank you for your answer. I was under the impression that the premiere carbs had the pilot jet in the same spot as the carb you drilled out and then punched out the pilot jet. Only difference being the jet is attached to a removable screw. But you say the plumbing is different and would have to be tapered also. Sounds like it's really not worth trying it. I hear you can drill out the plug, clean your pilot jet and tap the drilled hole and screw in a small substitute plug (maybe sealed with yellow Teflon or something. That way you can get to the back part of the pilot jet.( the side you were having an issue with. I believe you covered that in vid. Thanks again. Paul.
@@pauliebots Hi Paul, Regarding re-blanking the holes, I turned up a bit of alli with a slight taper to make the plugs and knocked them into the holes with a smer of Loctite. If I ever need to remove the plugs they will tap out from the other side with the air pilot screw removed, hopefully I won't need to though. Regards, Brian.
Hi Neil, I am way down South West just beyond Truro in a small village called Penelewey. What model is your 68 Daytona and where are you located? Regards, Brian.
It’s the 68 t100r American import, it’s my favourite bike you know when you get a bike that just fits and ticks all the boxes a real keeper. I’m based up north near liverpool. Got an old ex team tiger cub trials to work on next but this Daytona just puts a fat smile on my face. She’s not bad for an old tart
Lived in Great Sankey nr Warrington most of my life and worked for the Port of Liverpool for 14 odd years before moving to Cornwall. Always had motorbikes and used to be an all weather rider for commuting to work. Since moving down here the second bike I refurbed was a Tiger Cub, frame was a 1960 and the engine was a 63. I converted the engine to a side points with and end feed roller crank and later inner and outer timing cases, jap carb, RM21 stator and rotor electrics and electronic ignition, sprayed the tank in Bonni purple and silver. Always started first kick and very reliable, I sold it to get cash to buy the BSA B50, but still wish I had kept it. I have just finished a Cub engine for a friend who is going to use it for trials, fitted an RM21 stator to it and Wassel Vape electronic ignition. Also put the high sleeve gear in it so it has normal road speed gearing in 4th but makes 1st, 2nd and 3rd low ratio. Reminding me of my old Cub! just had a look on the DVLA website with its registration and the guy I sold it to must still be riding it as its taxed until May next year. Tiger Cubs are bringing good money, even for ones that need a lot of work as I have been looking for another, however I have just been to see a 1960 C15T trials, its all original with the trials gearbox, wide frame and swinging arm. It needs a bit of work which I have quoted for and he is deciding if he want's the work done or sell the bile as is, so could be the next project.
Excellent. Informative well presented and useful.
Thanks for your positive response, regards Brian
Brian , I'm a Japanese bike guy and once fixed a Bonneville with no idle , just blew air
through and it was good . Had no idea where the pilot jet was locared , just was lucky
it got cleared ! . 50 years later and I now have an answer !
Btw I today think these were the greatest bikes ever (they had the looks and can be made reliable enough ). My choice , the BSA Lightning 650, 1967.
I love BSA's and have a 250 B25 Starfire and a 500 B50T Victor, always fancied a 650 Firebird (Hornet in the USA) but never had enough cash, now getting a rare bike.
Great fix Brian. Here's another: If you have poor pickup from idle and fussy low speed running as I had on my T140 and particularly my T25T, file the flat part of the bottom of the slide, with radius to match the venturi, to a depth of 1mm (max 1.5mm) creating a sort of mini carb around those two tiny pilot holes. The improvement is dramatic. My T25T 250 Trail Blazer would often cut out pulling away from traffic lights and was hesitant and rough at low speeds. Now it pulls away smoothly and will bimble along at 2500rpm and speed up from there. Impossible before this simple mod. Experiment with old worn slides if you have some. I'm sure it will transform a fussy bike like the twin carb T100!
Hi David, did a tad more fine tuning and balancing on the the Daytona, now running sweet, could never get the B50 right at low revs and idle so bought a new Amal premier which sorted it out. However struggling to get the B25 right and have 4 or 5 spare slides, so will have a go. Regards Brian
Great video Brian, I have just bought my first 1964 triumph and there is lots of oil leaks to fix. You have got a great presentation style, makes it easy to follow you. Thanks heaps.
Enjoy you 64 Triumph, thanks for the kind words, regards Brian
didnt know any of that.....thank you for the info
Good tutorial Brian.
Thank's
Very informative info Brian I will do the mod .
Very innovative - Good luck!
Test run later today or tomorrow morning.
Hello Brian..great video. I didnt know the mach2 had the remote jet. I was also wondering if it was possible to drill out blanking plug tap, punch out jet and then tap the hole to fit removable jet like on the new premieres?Or is that pathway already too big?
Hi Paul, I did look at fitting a Premier pilot as I have a couple of 2 and 3 band jets in my spares box, however drilling the hole would be quite complicated as the jet runs through 90 degrees where the 4 holes in the side of the jet need to be inline with the cross drilling then at the bottom of the hole you need to have a taper to seat at the bottom end of the jet, plus behind the threads you need to drill a plain section for the jets o ring to seal against to stop air being drawn past the threads.
I think it can be done, I think that area is the best place for the fuel pilot restriction just before the chamber where the 2 small holes are drilled at the venturi as the carbs with the removable pilot jet above the float bowl seem to need a choke slide fitted for cold start as the restricted fuel flow has a greater distance to be drawn from the vacuum of the venturi and thats why Amal made the change to the pilot jets position on the Premier.
Regards, Brian.
@@TheCADengineer thank you for your answer. I was under the impression that the premiere carbs had the pilot jet in the same spot as the carb you drilled out and then punched out the pilot jet. Only difference being the jet is attached to a removable screw. But you say the plumbing is different and would have to be tapered also. Sounds like it's really not worth trying it. I hear you can drill out the plug, clean your pilot jet and tap the drilled hole and screw in a small substitute plug (maybe sealed with yellow Teflon or something. That way you can get to the back part of the pilot jet.( the side you were having an issue with. I believe you covered that in vid. Thanks again.
Paul.
@@pauliebots Hi Paul, Regarding re-blanking the holes, I turned up a bit of alli with a slight taper to make the plugs and knocked them into the holes with a smer of Loctite.
If I ever need to remove the plugs they will tap out from the other side with the air pilot screw removed, hopefully I won't need to though.
Regards, Brian.
Brilliant.
I’ve got to do this on mine, wish you lived next door Brian where are you based?
Hi Neil,
I am way down South West just beyond Truro in a small village called Penelewey.
What model is your 68 Daytona and where are you located?
Regards, Brian.
It’s the 68 t100r American import, it’s my favourite bike you know when you get a bike that just fits and ticks all the boxes a real keeper. I’m based up north near liverpool. Got an old ex team tiger cub trials to work on next but this Daytona just puts a fat smile on my face. She’s not bad for an old tart
Lived in Great Sankey nr Warrington most of my life and worked for the Port of Liverpool for 14 odd years before moving to Cornwall. Always had motorbikes and used to be an all weather rider for commuting to work. Since moving down here the second bike I refurbed was a Tiger Cub, frame was a 1960 and the engine was a 63. I converted the engine to a side points with and end feed roller crank and later inner and outer timing cases, jap carb, RM21 stator and rotor electrics and electronic ignition, sprayed the tank in Bonni purple and silver. Always started first kick and very reliable, I sold it to get cash to buy the BSA B50, but still wish I had kept it.
I have just finished a Cub engine for a friend who is going to use it for trials, fitted an RM21 stator to it and Wassel Vape electronic ignition. Also put the high sleeve gear in it so it has normal road speed gearing in 4th but makes 1st, 2nd and 3rd low ratio.
Reminding me of my old Cub! just had a look on the DVLA website with its registration and the guy I sold it to must still be riding it as its taxed until May next year.
Tiger Cubs are bringing good money, even for ones that need a lot of work as I have been looking for another, however I have just been to see a 1960 C15T trials, its all original with the trials gearbox, wide frame and swinging arm. It needs a bit of work which I have quoted for and he is deciding if he want's the work done or sell the bile as is, so could be the next project.