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Discussion Starter #1
Anyone know of a combination of camshafts etc. that shifts the torque of the stock 750 engines to lower revs giving a softer engine. The stock 750's are too revvy for me. I would have thought it was possible to get get much more low down grunt from these engines. I read that Triumph deliberately made them this way because the main bearings failed on the early 750's. Before owning my '77 TR7V I had a 1959 pre-unit Thunderbird. I'd like the Tiger to feel like that.
 

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The TR7RV gives lots of grunt/torque at lower revs... try a smaller rear wheel sprocket. I put on a 45 tooth in place of the standard 47 tooth on mine and it gives it longer "legs"...worth a try! There's even a 43 tooth option.
Cheers,
Richard
 

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I am not sure but I do not think 6T camshafts will fit. I have no idea how much it would cost to get yours reground to that profile, make sure you have the correct form tappets also.
Lowering the compression ratio wont actually increase torque that much , but it will allow the engine to be smooth at lower revs. I would do all three things if affordable.

The gearing is as already said very important. Err on the low side. Ensure it is not running rich on the first bit of main jet throttle 1/8th to nearly 1/2.

Also ensure you dont have any loose chains or worn rubbers in the transmission shock absorbers.

Check you have good valve seats and they dont leak. ensure tappets are not tight.
 

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Discussion Starter #5
Thanks for the responses. Anyone know of a 'softer' camshaft combination? I wish I could remember what cams were in my old 6T. Can you use 650 cams in the 750 engine? The compression ratio is already quite low at 7.9:1.
 

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The 1063 inlet and your standard exhaust cam set up as per the 6T will do the trick. Use standard followers as opposed to R type this will give better low end pull. Avoid lowering the compression if poss as this kills the performance.

Nick
 

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Avoid lowering the compression if poss as this kills the performance.
Nick
Lowered compression ratio was done by the factory for the Police spec bikes (the "Saint" model) in order to make the bikes more tractable at the low end and hence more suitable for city use. Gearing was also reduced in some cases.
 

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Discussion Starter #8
Thanks for all the great comments folks. I think I might try to find an E1063 inlet cam from a 650. I guess it will fit into the 750 cases. The timed breather slot I think was the only difference. Does the Tiger use std or R followers as stock?
 

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Lowered compression ratio was done by the factory for the Police spec bikes (the "Saint" model) in order to make the bikes more tractable at the low end and hence more suitable for city use. Gearing was also reduced in some cases.

The Saint had many forms often it just was a Trophy with different electrics and lower gearing. A pal of mine bought one years ago and we found that it also had a different exhaust cam but the pistons etc were all the same, just had very low gearing,
and a good alternator for the day.
 
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