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Discussion Starter #1 (Edited)
With the cold and wet weather making me not want to ride, it gets me into a tinkering mood everytime I walk through the garage. Now that the 1200 has been out for a little while and the aftermarket is catching up, I just want to hear what have you made/purchased/modified? What horsepower and torque figures did it get you?

Any and all performance mods welcome.
 

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With pretty basic mods - Meercat X pipe, US spec V&H pipes (baffles out), snorkel gone, BMC air filter, 17t front sprocket - my Thruxton goes just how I want it. The most positive of these is the sprocket change, making it more comfortable riding at highway speeds and it didn’t really slow off the line acceleration noticeably. In fact I think it’s a little quicker round town because I can use 2nd gear out of a corner where I previously would have been in 3rd. TEC cam might come but I’m not sure I’d use the extra top end very much if at all.

As for numbers, don’t know and don’t care. They’re irrelevant.
 

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I see Tec has a camshaft that is claimed to add a few hp.
My concern with that is wear. Over on the Norton site we see all kinds of performance camshafts wearing out prematurely. For example, one popular top end cam for those bikes is the PW3 or Peter Williams 3. The greatest mileage recorded so far with that cam is 25,000 miles. Most are done at around 15,000. When the lobes and lifters go the resultant grindings combine with the oil to form a grinding paste which takes out the crank journals, all bearings and often the pistons, rings and bores as well. In short, the engine is done, needing a complete rebuild. With the Thruxton 1200, I suspect it would be cheaper to find a good used bike than to do a complete rebuild on that motor.
With the Thruxton, the motor oil is common to the trans as well so the paste would also do it's damage there.
The good news is that most factory cams in modern engines last for the life of the engine, 150,000 miles or more.
I expect that Triumph engineers know how to make long lasting camshafts for use in their engines.
I'm not so sure about the aftermarket.

As far as power from the stock bike, it's more than adequate for me. On hard acceleration out of corners I see the traction control light flashing, which means power to the rear wheels is being cut due to wheel slippage.


Glen
 

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I see Tec has a camshaft that is claimed to add a few hp.
My concern with that is wear. Over on the Norton site we see all kinds of performance camshafts wearing out prematurely. For example, one popular top end cam for those bikes is the PW3 or Peter Williams 3. The greatest mileage recorded so far with that cam is 25,000 miles. Most are done at around 15,000. When the lobes and lifters go the resultant grindings combine with the oil to form a grinding paste which takes out the crank journals, all bearings and often the pistons, rings and bores as well. In short, the engine is done, needing a complete rebuild. With the Thruxton 1200, I suspect it would be cheaper to find a good used bike than to do a complete rebuild on that motor.
With the Thruxton, the motor oil is common to the trans as well so the paste would also do it's damage there.
The good news is that most factory cams in modern engines last for the life of the engine, 150,000 miles or more.
I expect that Triumph engineers know how to make long lasting camshafts for use in their engines.
I'm not so sure about the aftermarket.

As far as power from the stock bike, it's more than adequate for me. On hard acceleration out of corners I see the traction control light flashing, which means power to the rear wheels is being cut due to wheel slippage.


Glen
I wish my eyes were that good.:wink2:

Power is how you apply it.

Rode a mates Panagale V4 for the first time this morning through Bull Creek and the Ashbourne Road this morning....jeeeeesus.

Interesting thing was he rode my Thruxton R and was really impressed.

Now can I trust him with the Bimota?
 

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Discussion Starter #9
£21,500 ish serious money, I plan to sell my TTR soon with a mere 120hp for around half that.
What did you to go get 120hp? I'm going to guess x pipe, slip ons, pod filters, and a pcv with tune?
 

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Discussion Starter #10
I see Tec has a camshaft that is claimed to add a few hp.
My concern with that is wear. Over on the Norton site we see all kinds of performance camshafts wearing out prematurely. For example, one popular top end cam for those bikes is the PW3 or Peter Williams 3. The greatest mileage recorded so far with that cam is 25,000 miles. Most are done at around 15,000. When the lobes and lifters go the resultant grindings combine with the oil to form a grinding paste which takes out the crank journals, all bearings and often the pistons, rings and bores as well. In short, the engine is done, needing a complete rebuild. With the Thruxton 1200, I suspect it would be cheaper to find a good used bike than to do a complete rebuild on that motor.
With the Thruxton, the motor oil is common to the trans as well so the paste would also do it's damage there.
The good news is that most factory cams in modern engines last for the life of the engine, 150,000 miles or more.
I expect that Triumph engineers know how to make long lasting camshafts for use in their engines.
I'm not so sure about the aftermarket.

As far as power from the stock bike, it's more than adequate for me. On hard acceleration out of corners I see the traction control light flashing, which means power to the rear wheels is being cut due to wheel slippage.


Glen
You always take the same risk with parts from the aftermarket or OEM. As a professional mechanic I've seen cars and trucks with 1000 to 30000mi that had a failing Cam, hydrolic lifter, rocker arm or push rod failures with perfect service history. I had a Cam snap in half on my old BMW 3 series. But just like a lot of things, it's into you if the risk is worth the reward.

I made this tread because I'm curious on what people are getting out of these motors and how they got there. After all, anything with a motor is a grown mans Lego set.
 

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Lobe wear shouldn't be a problem on the W/C engines. The rocker has a large roller riding against the cam lobe, minimum friction.

The Norton on the other hand has a narrow flat lifter that dose not rotate like most round automotive lifters riding against slightly tapered lobes to promote
rotation and reduce wear.
 

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... oh & dump the x pipe for proper headers.
LOL, don't you start! Adding straight headers reduces power. Let's not keep propagating this "alternative fact", there's enough dodgy information out there as-is.
Next we'll be back to the virtues of Booster Plugs to richen up "the lean running engine" and "release the power" :D
 

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LOL, don't you start! Adding straight headers reduces power. Let's not keep propagating this "alternative fact", there's enough dodgy information out there as-is.:D
On a relatively stock motor 2-2 pipes maybe so, but I was refering to my worked head & big cam motor with higher rpm, on which I use headers with link pipe so there is still some scavenging.
I do not wish to try it but I am pretty sure if I put stock exhaust back on with those small pipes & four 90 degree bends my motor would lose power.
My TTR was at 89hp with decat, 93hp with Arrow headers & modded stock cans, but this was different days & dyno's.
I try to quote what works for me, & I have pcv on four of my triumphs to get the best from them, good dyno tune is always best, not the cheapest but you know it is at optimal efficiency.
So I will not be rushing out to get a booster thingy. :grin2::wink2:
 

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Yes, it was probably related to the conditions. Straight headers reduce the mid-range torque, not severely but the mid-range dips to about the same as leaving the cat in, then at the top end it comes back up to the same as an x-pipe decat.
The peak HP is always pretty meaningless for comparisons. The peak HP can bounce around by 3-5hp simply by having a loose chain or by reducing smoothing on the chart, but comparing the area under two torque curves gives you an excellent idea of the effect of any change.
I've seen a few exaggerated claims showing dyno runs with spikes from slippage or chain slap where the peak HP shows the top of those spikes, and that's why it's really just the torque curve that matters.
 

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LOL, don't you start! Adding straight headers reduces power. Let's not keep propagating this "alternative fact", there's enough dodgy information out there as-is.
Next we'll be back to the virtues of Booster Plugs to richen up "the lean running engine" and "release the power" :D
Thats interesting.

Consider that the alternative name for an exhaust system is an attenuation system. Attenuation is a refuction of force, in this case the output of the engine.

However, a secondary function is in reverb tuning. Reverb is a reflection force and assists in both attenuation and concentration. It is my understanding that this function is what gets removed when pipes are straight through.


Third time trying to reply - keeps saying token has expired.
 

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Let me get this straight. If there is insufficient attenuation of the reverberation the result could be a concentration of the propagation. Is that a reasonable summation of your contention?
 

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Discussion Starter #19
Let me get this straight. If there is insufficient attenuation of the reverberation the result could be a concentration of the propagation. Is that a reasonable summation of your contention?
Off topic but reading the last two post all I heard was "conjunction conjunction, what's your function" lol.
 

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...
Consider that the alternative name for an exhaust system is an attenuation system.
...
I don't think that is true. An exhaust isn't there to attenuate anything, it's there to move burnt gasses to a safe exit point. Power loss may be a side-effect of a cat or muffler, but their purpose is emission and noise attenuation, not power.
The idea that removing an exhaust pipe will make things work better is misguided. The effects of scavenging are factored into the cam timings, and removing interaction between the two exhausts is removing the scavenging that each cylinder experiences from the other.
The gains from removing the 90° bends at the x-pipe entry and exit don't come anywhere near the losses from the missing scavenging, as shown on all our dyno runs, and the fact that the top end power in unchanged (when the gasses are at their highest velocity) suggests that the straightening of those bends has no effect on the results, probably because the ports in the head are so much more restrictive.
 
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