Some Progress In Finding More Engine Performance

John. Was just comparing your graphs to those from Tec on the 900. Would appear the 900 has no built in throttle pull back as you find on the R and certainly no mention of it in the video.This would make sense as the restricting single throttle body could most likely do the job single handedly. Also on your first graph the stock hp line seems to affected more by pull back than the modified line. Is the increased air flow of the modification making it hard for the throttle plates to close as the much as the ECU would like ? What is the mechanical system used to do this ? If the smaller engines have no restriction system , it would certainly explain why they are finding it easier going than the 1200 cc guys.
 
I agree Brooke. For those of you that are only interested in eliminating the easily and inexpensive HP restrictions removing the cat, a power commander, and removing the top section of the intake are the way to go. If you like the V&H mufflers you can lose a little weight and get a throatier sound but they DO NOT ADD HP & TQ at this level of modification (particularly if you leave the sound pligs in). The stock mufflers perform as well until you get over 98 to 100 rear wheel HP. We found this in dyno testing when both exhaust systems are properly tuned. Raisch in Germany found the same thing and that is the reason they do not include aftermarket mufflers in their performance kits for the Thruxton R. I bought and tested Arrow head pipes which are larger than the stock Triumph head pipes and they eliminate the cat & the need for a X pipe. This DID NOT increase HP & TQ in fact it reduced power. The Arrow head pipes appear in the advertising to have a crossover pipe but in fact it is just two pieces of tubing welded to the outside of the Arrow head pipes with a slip fitting in the middle. We drilled out the inside of the Arrow crossover and then the bigger Arrow head pipes performed better than the stock head pipes. Why is this? The answer is that the inlet size of the stock mufflers or any aftermarket set of mufflers are to restrictive and you need a crossover pipe ahead of the mufflers to allow the engine to use both mufflers. This is particularly true if you use the rev extend feature on the power commander to raise the rev limit on the motor.
 
QUOTE="brooke, post: 274186, member: 3732"]John. Was just comparing your graphs to those from Tec on the 900. Would appear the 900 has no built in throttle pull back as you find on the R and certainly no mention of it in the video.This would make sense as the restricting single throttle body could most likely do the job single handedly. Also on your first graph the stock hp line seems to affected more by pull back than the modified line. Is the increased air flow of the modification making it hard for the throttle plates to close as the much as the ECU would like ? What is the mechanical system used to do this ? If the smaller engines have no restriction system , it would certainly explain why they are finding it easier going than the 1200 cc guys.[/QUOTE]

Brooke the throttle plates on the new 1200 Triumph's are fly by wire (the ECU controls throttle plate opening with a stepper motor built into the throttle body's). In other words the ECU controls throttle plate position and there is a throttle plate sensor that feeds back throttle position to the ECU ensuring that the TP position follows the ECU programming. When you tune with a power commander you can see the throttle position on the power commander software which uses the feedback signal from the throttle plate to show this. As you spin the motor up on the dyno you can see the throttle position go to 100% open and then back down to 85% when the RPM reaches the Triumph ECU's programmed limit. This happens at 6,700 RPM in one ride mode and 7,000 RPM in the most aggressive ride mode. In either case I suspect they did this to soften the power cut when you hit the stock 7,200 RPM rev limiter.
 
Very informative thread.
Just wondering, if the only changes made to a TTR are the installation of a Motone de-cat and upgrading the intake, is the ecu resetting procedure adequate, or is the Power Commander V necessary to compensate?
 
Sorry for the delay in getting the few remaining changes to try and pull a little more power out of my Thruxton R without getting into the motor but I have been very busy. All the remaining changers are on my work bench and it will probably be the end of May before I get them finished and do further dyno testing to verify whether they work.
 
No hope of getting this work done soon myself so I took the bike to Commonwealth and asked Chad to take care of it next week if possible including dyno verification. I am an optimist but Chad is a realist & since the weather here has taken a sharp turn toward hot & humid he advised that even corrected SAE dyno numbers may not show much. We shall see. Nothing major done this round.
1. Larger Raish radiused air box inlet (more airflow hopefully)
2. 520 chain & sprockets (lighter & less friction loss)
3. Ailsyn race oil & Petron additive (less internal friction loss)
 
Ok Chad finished the changes and we have a dyno sheet. The results are not overwhelming but I did not expect them to be. HP and TQ are up almost all the way across the RPM band. This is the result of the changes we just made. The red line run from 10/20/17 was the last run before these changes. We were successful in reducing engine & drive line losses. No changes were made to tuning or the motor. This is the final stage of this project for me unless some genius figures out how to re-flash the ECU to eliminate the throttle restrictions. I hope this has proved informative for those interested.
Triumph Thruxton Dyno run 5-23-2018.jpg
 
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One interesting aside to this last trip to Commonwealth to pick up my Thruxton. When I walked back in the shop there were two Indian flat track grand national bikes there. One on the dyno and the other sitting in the shop. They were there with a guy from the Indian factory flat track team doing testing on Commonwealth's dyno with Chad.
 
Thanks:oops:
 

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Thanks for all your work on this file John. Hopefully sending you photo of a 1970 ish AA/ Fuel CB 836 we found on our Appalachian.trip. Built in Detroit I believe ,the second of two this being the more refined of the pair , the first won races at the national level but in the end was a test mule for this one which was completed just as the team suffered a major split. Not sure if it ever made it to the track. 180 mph was what they did back then according to the present owner. Thanks again. Brooke94BDE2C2-1ABD-458D-81F2-9E4CE21D4B34.jpeg
 
Thanks for the photo Brooke it brings back memories. I built a 836 1977 Honda with a American Turbo Pack turbo kit. That bike would pull all the way to 11,000 RPM in 5th gear and would have pulled further until it came apart if I had not let off it at that point. Have no idea how fast that was but pretty scary on a unfaired bike.
 
By the way . I finally found the ambition to look at the air horn on the R . What’s with the inner end of it being so long it must almost touch the far side of the air box . Could it be to long ? You shorten the outer part about half down , correct? Are you thinking that the hole in the box that tube goes through and of course the tube it self could be larger?
 
We removed it entirely and replaced it with a part made by Raisch in Germany. This simply a new radiused inlet that fits directly over the entrance on the side of the air box. It does not increase the size if the air box it just provides a smooth radiused entry directly into the air box without the 90 degree bend and the longer path of entry. The idea is less turbulence as well as a shorter path of entry.
 
That makes sense . Will work work with that thought . Thanks again
 
Brooke the picture of the turbo 750 Honda shows a log type exhaust manifold just like the early production American Turbo Pak kits. The ATP boost blow off valve was also located in the same place on the exhaust manifold & looks very similar based on my memory. The rest of the exhaust system in the picture is different from the ATP system for the 750 Honda. ATP later went to a 4 into 1 exhaust manifold on the Suzuki & Kawasaki kits that had short primarys into the 4/1 collector. First time I saw one of these run was a Kawasaki 900 that ATP brought to the NHRA nationals in Bowling Green KY. This was a stock looking 900 Kawasaki down to the turn signals with the ATP kit installed. It was ridden by pee wee Gleason a rider used by the cycle magazines and all the Japanese mfgs. at the time for 1/4 mile testing (this guy didn't weigh more than 130 # dressed to ride). He went to the starting line with the 4 way flashers on and did a demo run at 148MPH at 9.80 seconds. This was as fast as Terry Vance's RC Engineering pro stock bike ran and This was what convinced me to build a ATP turbo engine for my 77 Honda SS. Forged 8/1 836 pistons, Carrillo rods, Yoshimura valve springs & retainers, crank & rods balanced by RC Engineering. The engine held together for four years of hard street riding as well as drag strip use without a failure and I sold it to a friend in 1981.
 
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John. Certainly remember the name pee wee Gleason, wish I could remember everything from the day we saw the green Honda. Do recall that the predecessor was referred to as the white bike with several articles and photos,the tank was indeed painted white. Brooke
 
better late than never dept. Just heard on another forum that Hilltop racing has supposedly unlocked one of the WCTs ECUs, not sure which one 900 or1200. But it was also said they are not forthcoming about sharing the joy.
 
Had to happen .You can hack anything these days . Even the Russians can hack a few basic things . Brooke40D02C21-B63D-42CE-82C5-8B8B5CA937E6.jpeg
 
Brooke thanks for the information. I will inquire again about the re-flash from Hilltop. Last time they said no
 
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