long stroke crank and con rod

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roadrunnerian
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thinking of going long stroke on my ts1 whats the best combination thanks
Adam_Winstone
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...Deep pockets and an AA membership.

Kidding. I'll watch to see what others come back with as I don't really have an answer but would watch responses with interest to see what people come up with.

20+ years of tuning Ts1 resulted in the most popular road tunes being Taffs use of 110 rods, with a combination of head work, and MB's machining off the base area - both of which reduced transfer timing from the standard TS1 durations. More extreme states of tune, with less road ride ability, kept the long transfer timing and increased exhaust port duration, but this results in a very peaky engine that is not so road friendly :(

In light of the above, increasing stroke on a motor will lead to an increase in transfer duration and will only make a peaky motor even peakier and nastier to ride on the road, unless you want to thrash it everywhere. The increase in cc that increasing stroke gives does not negate this peaky delivery so be wary if you are hoping to give it more grunt. If you want more grunt then you need to increase stroke AND get the porting right with it.

It's horses for courses but you need to confirm what result you are hoping to achieve, then others might be able to give you detailed advice of how to make it happen.

Good luck in your quest.

Adam
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drunkmunkey6969
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roadrunnerian wrote:thinking of going long stroke on my ts1 whats the best combination thanks
For ease of fitting and increased packer choices.....60/110. Excellent option for budget, performance and price.

For big cc and more tuning options 62/116. Potentially greater gains, but is a more complex option.
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Train Driver
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Don't listen to those old women ;)
64mm with a 120mm rod from MB, a bit vibby 8-) not many pistons 8-) err that's it
I did hear JB were doing 63mm & 65mm but that was a year ago.
TS1 and PX stay in the garage (future barn finds) out on the GTS 300 when I go out on a scooter.
I know I’ll get there and back
Adam_Winstone
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;)
roadrunnerian
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thanks for the replies so far everyone, anyone else with ideas, at the moment i'm just looking to add a bit more bottom end. :D
Adam_Winstone
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I thought as much. Do note what I've said about needing to take port durations (as a result of increasing stroke). Also take note of what DrunkMonkey has said about the ease of fitting a 60 with a 110 rod (allowing you to address prt durations by adding packers to top or bottom of barrel. Also, make sure that you ignore everything Train Driver says (lol)... Only kidding, however, his very good MB option cannot be applied without considerable modification to casings and a lot of barrel work/consideration.

I have a number of long stroke motors (65mm and two 62mm) but these have all had extensive casing work (welding and machining) and none of the motors are simply bolt on barrel options. The good thing about DM's 60/110 suggestion is that it can (subject to crank choice and co rod big end spec) be fitted without casing modification and does give room for you to move the barrel up or down to influence (limited though!) port durations.

If you simply want a bit more grunt then you might be best off considering other factors before looking to increase stroke, e.g. exhaust choice, reed options, etc.

Adam

Ps - do note that a change to 58mm stroke with 110 rod may actually suit you just as well, if not better, as the ability to 'place' the transfers where you want them could give you the lower duration that returns more grunt. MB has good info on this in his TS1 tuning pages of his site and Taffspeed used to cover this in detail on their old website but I'm not sure if this is still accessible on line.
johnd
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Doesn't fitting a five speed gearbox cure the peaky TS1 problems?
But 60/110 would be my choice for the cubic capacity and transfer timing options.


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Architecten
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I have a MEC 60x110... good value at £130!
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wack 63
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Easiest is machine the base gasket face but 60/110, no base gasket or the thin AF 0,1mm alloy spacer then a thick head gasket is the next up.You could try a 115 rod on a 58 stroke and use a combination of different base packers to keep the port timings lower than standard ie 7mm instead of the normal 8mm,then make up the difference with the head gaskets or head machining.Interestingly the ones I have done for mates with the 60/110 combo leave me standing from the lights etc but my 115 blows them away once in the power but uses more fuel compared.A 62/116 motor I did for a mate only made 20 hp on the dyno at Newark rally but had 22ft/lb torque, and the operator said it was the nicest road tune he had dynoed that day,it was using a standard cylinder and a devtour and built for grunt.
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