Pre-65 Bikes

Would anybody have written down what the ammount of teeth on 1st 2nd 3rd and 4th on Cub trials gearbox, plus front primary, and chain front and back had everything written down myself and put away somewhere, and now cannot find the stuff☹️ Vinnie

I have been asked by a French chum, who is building a Trifield, if I could find out the gear box ratios, and also the sprocket sizes that people in the UK use. Also once found, who could furnish such items. Appriciate any help as he hope to ride in Scotland next year, after struggling a little on his big Terrot. Merci.

Hi guys got a nice 400cc twin Problem is that its "wet supming" all the time Have just fitted a new morgo pump to cure but is not any different any ideas?? MartyD I could fit a tap but think that would be the last resort as im likley to forget to open it!!!

I have a Triumph 5TA distributor engine in a trials frame, and currently have the engine out for repairs. I have noticed a lot of twins with breathers out of the dizzy mounting hole. When making this mod do I blank off the original breather, and remove the associated disc valve?, or do I run both systems? I always worry about water entering through the original breather when in deep water sections, but I have never seen any evidence of this happening. I would like to alleviate this worry, if I can. I have also seen a few bikes breathing out of the primary case, I presume this means taking out the seal between the crankcase and primary, but does this include drilling a ho…

Hello there, My 3ta engined trials bike has suddenly decided not to run unless on full choke. I've stripped and checked the carb a couple of times, float and needle are OK, tank and carb. filters are clear, tank cap breather is clear, replaced jets, needle and gaskets but no joy, it splutters out as soon as I begin to open the choke. Exhaust pipes are tight, can't find any evidence of cylinder head leaks.The plugs are obviously sooty black with the choke on. The bike has a Rex Caunt ignition system. Any suggestions would be welcome, no matter how unlikely they may sound!. Regards, Bulltaco.

Hi everyone, I have recently got hold of a triumph 3TA twin engine basket case. This will eventualy be slotted into a royal enfield 250 crusader trials frame to make the popular TriField or Tri Enfield machine. Has anyone out there built one of these bikes, and if so what would be the best engine specification to go for - 350 or 500, There are a lot of tuning options from stock 350 to Daytona 500. etc Any info and advice greatly apreciated. Jon Summerfield.

Hello everybody, I am currently building a triumph twin (500) into a Whitlock frame, and would like some advice on sprockets. The engine is currently on standard sprockets, and I need to try to keep the rear(wheel) sprocket small, as it's quite crowded back there. That suggests I need to use the smallest driving sprockets available, which are 13t gearbox, and 16t engine. BUT I don't want to be having to tackle sections in top gear if I go too far, so- the question is, has anybody out there got any experience of the optimum sprocket combinations for a Triumph twin?

I've recently got a norton frame with a triumph twin in it. It came with the electronic ignition bits tied to the bars, with no diagrams, so i'm a bit stuck with wiring. From the stator there are two wires, Blue and Black. The coil (with the two HT leads coming out, has two connectors. There is another smaller box, this has a Red, Brown (which i assume is to earth as it had a ring crimp on the end), and a lead coming out with Blue and Brown wires, these have crimps on the end, that are easily accepted by the coil's two spade connectors. I have no wiring diagram for this, so really need some help. If it help's i can get some pictures of the components. Cheers, Kelvin…

I have the bare bones of a triumph T90 and would like to know what subframe would fit the main loop without much modding as the bathtub original isnt what im after as its far too wide . I have seen triumphs with cub and c15 type back ends ,thanks

I know Serco is the place for Cub engine work but who's the guru on frame/fork mods. And who supplies parts and info for trials Triumph unit twins and BSA C15s/B40s?.

"I heard a rumour, it was just a rumour..." great song btw. Siouxsie & the Banshees... Sorry back to topic. Does anyone have any news regards tubed tyres, are they being phased out? I understand stocks of tubed IRC's are far and few between. Would be interested to understrand the options, tube in non-tube tyre, tubeless??

thinking of putting tubeless rims on a new bantam build and would be pleased to hear any comments or suggestions good or bad thanks.

.... bring on the Guy Fawkes trial. Might even try to get it painted before Sunday, am thinking black, with Silver coach lines and the obligatory flying 'M'.

Thinking of trying a triumph twin trialer,What motor should i start with???? Everone i have spoken to with a 350 says the 500 is too powerfull and the boys with 500 say 350's wont grip??? I know it is a matter of taste but whats your opinion??

changing from one frame manufacturer to another.. and using the same njb tricshoxs which were perfect on the old frame. on the new bike the mounts mean the shock is markedly more 'laid down' and although the bike 'sits' at the right height 'unladen' once my weight is on it the spring compresses almost to the stops. does laying the shocks down make the spring action softer? do i stiffen them up and or lengthen the shock at the same time. given the price of a pair i only want to do it once...

hi ive got a dilemer with my clutch what it is is that i start the bike up and then pull te clutch in and put it into gear and it pulls away without even letting the clutch out

Just about got the Bantam finished and was wondering what tyre pressures to run.My bike is a D7 running Pirelli tyres,I was giving a figure of 6psi front and 3/4psi rear,but is it ok to run them that low with tubes?? cheers the noo Brian

Has anybody any experience of tyre sliding of rim (Triumph Cub) normal 18" wheel new tyre 2 tyre clamps tube type tyre and rim HELP Vinnie

Can someone advise me what tyres are available in (or around) 3.00-19 and 3.25-19 for my DOT.Insert other media

Can anyone recomend which tyres works well on Pre 65 and should they be used with a tube or tubless