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Thruxton R, full system, PCV and Autotune - experiences?

23K views 41 replies 12 participants last post by  roffe_s 
#1 · (Edited)
Hi,

As I earlier have tuned quite a handful of bikes with Tuneboy, TuneECU, Bazzaz and Powercommander with the help of WBO2, I just cannot keep my fingers away from the Thrux any longer. So on order is Arrow headers, Shark Shorties and PC-V with Autotune.

Now, I aint that interested in particular dyno HP numbers, more of the target AF for a large twin as the Thrux engine. Have anyone in here dynoed Your bike and made a couple of proper runs to find optimum A/F? On my sportbikes, I've normalt found that AFR 13.1 - 13.3 on 100% throttle seems to be optimum and I expect that a large twin would run best on a slightly richer mix. But it would be of great help if someone could confirm the thoughts :)

The tunes provided by Powercommander looks quite reasonable with a lot of added fuel in midrange/part throttle (emission) and about 10% in midrange/full throttle. I'll probably use their British Custom exhaust tune as a basemap for my own tuning. Is it anyone with a mounted PC-V who may confirm the choice of base map for a full system?

Nevertheless, the R is a really nice bike. However, I cannot stop thinking about if and when Triumph would release the race cams that we heard rumours about more than a year ago... :)
 
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#3 ·
I'm beginning to suspect that "tuning" just requires fitting the parts, disconnecting the battery for ten minutes, and then starting her up to start an ECU relearn.

If the ECU is good for up to a 15% positive fuel mix adjustment with the stock sensors, that should handle just about any exhaust mod you could mount up.
 
#4 · (Edited)
Thank You for the answers! I hear You, but I still havent seen a proper explanation about HOW the ECU should know in which area to add or withdraw fuel? Which sensors avaliable should indicate a proper mixture? The stock O2 NB sensors are not able to analyze if the mixture is anything but richer or leaner than stoich AFR of 14.7 and is therefor only used in closed loop condition (small throttle openings, steady conditions).

I havent been able to find out that the Thrux ECU is equipped with any other options than other Triumphs, and according to my knowledge and experience they are only adjusting fuel during these closed loop conditions, conditions never used when we are on full throttle. The adaption process after reset or disconnected battery is just this - the bike learning and adjusting the closed loop fuelling on idle, it doesnt impact cruising or accelerating zone of the tune.

By the way, the closed loop conditions and the fact that the fuel tables on small throttle openings is indexated by manifold air pressure instead of throttle position is the reason for Power Commander to use O2 eliminator plugs and advise us not to mess with the fuelling in the lower throttle openings (1-5%).

Of course, it is fully possible that the stock fuelling tables works descent with decat and slip-on. But we dont know, not until we see a AFR-log of the bike. Normally, You get most gain in midrange and in a smooth power delivery with a proper tuned bike, and that is what I want to ensure. Only judging of the few dyno sheets from full systems avaliable, the official tunes from Power Commander and the sound in a few videos avaliable of decat bikes, I believe that there are benefits to gain with a tad of tuning.

But we will at least know in a while. Here in the northern parts of Sweden there is still snow on the ground, so I will probably not be able to test anything until may.
 
#12 · (Edited)
...I still havent seen a proper explanation about HOW the ECU should know in which area to add or withdraw fuel? Which sensors avaliable should indicate a proper mixture? The stock O2 NB sensors are not able to analyze if the mixture is anything but richer or leaner than stoich AFR of 14.7 and is therefor only used in closed loop condition (small throttle openings, steady conditions)...
Yes, there are so many postings with people saying "The ECU adapts to the new ...", but to me this is akin to arguing the existence of your chosen religion's deity.
I see nothing to suggest the ECU has the ability to 'adapt' with the exception of the O2 sensors and the throttle position/MAP sensors. I know the O2 closed-loop system works well, as no matter how much you bugger around with the exhaust restrictions, you still get almost exactly 14.7 at idle, cruise, and gentle acceleration.

Open loop clicks in at anything more than gentle acceleration, and not only on full-throttle. The narrow-band sensors do indeed simply provide the ECU with a means of doing a lean/rich cycle to keep it at stoich, as there's no other way when you have a sensor that can only say either "too high!" or "too low!" :)

When the throttle's cracked open by more than about 10% the ECU uses the open loop map, which contains timings for the injectors, not a target A/F mix. This means if we open everything up to improve flow, the injector provides the same fuel as if we still had the cat, snorkel, and restrictive airbox intake. As per your questions, I think suggesting that the ECU "knows" this stuff has been removed is like when my wife argues I should have "known" that she needed me to pick up milk at the shops!

What's impressive is that even then we seem to get a very acceptable mixture, with no sign of the claimed "lean running" that is prevalent in forum discussions.

I've not used an autotune module on my PCV. I did mine on a dyno, and got a flat ~13.5 at full throttle, which while slightly on the lean side of power, appears to be optimal for my engine. I'm still experimenting with timings, which are not touched by autotune modules anyway, and I currently have a 5% advance on everything above 10% throttle. I'll fine tune this shortly, but this gave better responsiveness than stock for now, although it does need 98 octane fuel otherwise it pings at 2500rpm when the throttle's cracked suddenly.

If we can manage to crack the ECU data we can disable O2 sensors, which means we won't have maps being transitioned between, and that would mean even the PCV would be easier to manage because it would always be relative to a single base table. It would also be awesome to be able to fit a PCV, tune it all up in real-time, then apply the new variation tables directly to the ECU maps!

Anyway, I'm with you on the big question, and I hope that at some point I can get access to the Keihin ECU contents. I'll let you know if I do :)
 
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#5 ·
In order to comply with emissions requirements most new machines operate in closed loop over all conditions except full throttle. The primary reason full throttle is not left in closed loop mode is the danger of running weak in the most stressed part of the operating range. Most manufacturers therefore run slightly rich at full throttle. In order to be effective devices like the PCV will override the closed loop by tweaking the lambda sensor values by some means so that the closed loop control is kept happy even though combustion is power/torque optimized rather than emissions optimized.

Without other engine modifications the majority of after-market intake and exhaust modifications will not increase air flow through the engine except in very specific rpm ranges and even then the changes are usually quite small so its quite plausible that the closed loop fuelling maps are able to maintain their target A/F values in most cases. As full throttle tends to be mapped a bit richer than necessary this will also be OK in most cases, and in fact many systems which are not developed through dyno testing will actually flow less air at full throttle and need to be weaker for ideal power.

Having used Powercommander and other products on several different machines I have to say that the real benefit is in terms of throttle response and driveability so if you have no issues with these aspects after your other modifications it may not be a worthwhile investment.
 
#6 · (Edited)
In order to comply with emissions requirements most new machines operate in closed loop over all conditions except full throttle. The primary reason full throttle is not left in closed loop mode is the danger of running weak in the most stressed part of the operating range. Most manufacturers therefore run slightly rich at full throttle. In order to be effective devices like the PCV will override the closed loop by tweaking the lambda sensor values by some means so that the closed loop control is kept happy even though combustion is power/torque optimized rather than emissions optimized...
Well, at least with the earlier Keihin ECU and Euro 3 this was not the case as we were able to trace when the ECU was working in closed or open loop with software like Tuneboy and TuneECU. And the bikes with Keihin I have tuned (Daytona 675, Str3, RC8, Gsxr) is just not running properly on even small acceleration movement with AFR leaner than 13.5-14. And as I cannot see any wide band lamda sensors on the Thrux, I just have to assume that closed loop still isnt used in other conditions than steady state at low throttle positions.

But I guess we will know more when we have a couple of runs :)
 
#8 · (Edited)
Hi Nick. That is a great first post and jsobell know his stuff. I dont think anyone of us argue about that the ECU doesnt adapt - it have done so during many years, as long as Narrow band lambda sensors have been used on our bikes. The thing is that the bike with NB sensors is only capable of adapting to a very lean mixture of 14.7 - not usable for larger throttle positions. A bikes ECU is still quite simple compared to a car and the setup I have found on the R simply lack the sensors to adapt to a richer mixture (like 13 - mentioned in the thread). Jsobell is describing exactly the same facts in one of his later posts in the thread.

But this is not a big deal, as long as the fuelling of our bikes is within the ballpark with a full system mounted. There seems to be some dyno runs by Fenech with the PC-V in the near future, will be interesting to follow :)
 
#11 ·
Its not necessarily the case that narrow band lambda sensors cannot be used throughout the whole envelope. Though they are only sensitive to one particular oxygen concentration the ECU monitors the crossover condition and this can occur on every combustion cycle ( although I'm not sure if they can respond that quickly ). So there is no reason that the ECU can't work by a sort of trial and error process over the known actual response time of the sensor. For example increase the fuel - wait for sensor reaction - change fuel in response. As this can be done within a few cycles it would seem smooth enough even though its actually making step changes. This is why fooling the ECU that the A/F ratio is within the target is not as simple as changing a static voltage or impedance. You have to simulate the cyclic behaviour even if the sensor itself may be permanently below its oxygen threshold because you have richened the mixture. Of course once you do this the lambda sensor does become redundant until you allow the normal behaviour to resume which is normally just for a smooth idle condition. If the lambda sensor is changed then a self-learning system can come into play with different A/F targets and this is what the more expensive Powercommander autotune add on offers. A wide band sensor gives more flexibility and is presumably more readily available than a narrow band sensor with a lower oxygen target range.
 
#13 · (Edited)
Eastern Bunny came early this year and why wait, opening the eggs? So now I know what to do for a couple of hours during the upcoming holiday :)

Anything particular to keep in mind during the installation on the bike? As Triumph havent released the workshop manual and I just cant find myself the time to open files and printing pdf:s for half a day, I'll try to figure it out myself :)
 

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#14 ·
@roffe_s It looks like you have Arrow Collectors # 71658MI. I am confused by the design of them after looking at photos. Did they include a collector pipe extension? I see the flanges on the headers themselves, but they are not long enough to connect under the bike without an additional cross pipe. At least that is what the photos suggest.

As far as your installation, you'll have to remove the existing catalytic converter as per here:

 
#15 ·
@roffe_s It looks like you have Arrow Collectors # 71658MI. I am confused by the design of them after looking at photos. Did they include a collector pipe extension? I see the flanges on the headers themselves, but they are not long enough to connect under the bike without an additional cross pipe...
Hi Delta, Thanks for the link. Especially the fuel line collector use to be a PITA so this video will be helpful :)

The extensions on the Arrow collectors is just dummies for the look, the collector pipe is sealed and without opening at the extension.
 
#18 ·
Well...
1. No, it's standard on all non-cat bikes. Plus a 3.5kg cat puts way more vibration on the headers than the arrows or a cross-pipe
2. No, the cat is rubber mounted, so provides zero support
3. I don't think so. It looks like any other bike with an engine at the front :)

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#21 · (Edited)
Okey, this evening I made the first base run with the new config and Autotune. As I live in northern Sweden, temperature was only +2 degrees C when i did the first session. The bikes ECU is normally overcompensating the fueling in cold conditions, therefor I expect the final map to become a tad richer when temperature rises above plus 10 degrees.

However, the run was good with logging in all interesting parts of the map. Already after the first run, there seems to be some conclusions to be made:

1 - There is a healthy amount of power and smoothness added through the powerband with a custom tune and full system.

2 - As expected, the most significant difference between the X-pipe and Arrow headers is on part trottle in midrange (maybe the missing pipe between the headers have an influence?). On full throttle, the fuelling is almost identical.

3 - The base tune for the Thruxton must be very good, the best I've seen so far as an OEM tune. There seem to be no risk for any engine damage due to lean conditions with the OEM tune, however smoothness and rock steady torque development is improved with the custom tune.

Nice first run, I'm very satisfied with the result of the modifications so far :)
 
#22 ·
Great thread, I recently rode my Friends thruxton r with the arrow headers and Remus rear pipes with a pcv, I didn't see the dyno sheet but could feel the midrange improvement over the stock bike, noticed from the yt clip you've posted it has the same throaty sound as my friends bike, seriously considering the arrow headers although as Jason has pointed out in seperate threads the the flattened curve in the front Lower pipe looks a little weird, it prefer if it had the same curve as the stock pipes.
 
#25 ·
Huy guys,

Just wanted to let you know that I have 2 Black REMUS sets available for the Thruxton/R 2016-!!! These are the first 2 Black sets available in the US. I know that many were interested in that particular finish. I'm offering these systems to Forum members first. You can either contact me directly or put in an offer on our ebay listing: http://www.ebay.com/itm/-/132180061320?

Here's a picture:

 
#26 ·
For You that have asked for WB sensor mount on the bike, I hereby attach a picture (which I cant rotate to fit in the post) showing the mount on the #1 header.

One thing to notice is that the Arrow downpipes seems to be a little wider than the OEMs and therefor limiting the lean angle a tad. I noticed this in a quite harsh way, riding the Thrux like a sport bike during a track session... :)

I must say that the automapping process have been really smooth so far, with the important sectors of the map dialed in after only 3-4 sessions on the road. The engine is as smooth as powerful during all conditions now and I have only been adjusting the small throttle openings lately. The sound is awesome, but I have my doubt that the dB-killers will be enough when it is time for the mandatory inspection here in Sweden...>:)
 

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#28 · (Edited)
This setup would offer a tailormade fuel tune to You with Your Street Twin as well as every other bike that is compatible with a PC-V.

But it is not a total plug and play solution. You need to know a thing or two, f i about:

1 - What will be Your target AFR? In every part of the tune.
2 - How to do Your tuning sessions. Forget about "just go out on the track or on the street and do Your regular driving", too much contamined readings (especially from engine braking with partly opened throttle) will not give You a good tune.
3 - be suspicious while analyzing Your tune. Keep in mind that strange things often occurs in the part of the tune where You normally apply or remove throttle. Nearby cells might interfear with eachothers, it is mostly wise to smoothen things out during evaluation of a tune.

Today the manufacturers dont release bad tuning from the start, they are quite good. Your gains with a custom tune is first and most important a really smooth behaviour during transitions on/off throttle, a very steady torque curve and perhaps a couple of horsepowers on top, a couple more in midrange.

Good luck if You decide to give it a try :)
 
#32 · (Edited)
Rapid Bike?

I've been reading thru a few of the threads on here about exhausts, cat deletes, piggybacks, etc, and have found no mention of the Rapid Bike modules. Anyone on here have any experience with them? I looked on the Rapid Bike site, and they offer systems for up to '15 Thruxtons, but not the 1200s. I emailed them to see if one is in the works.

There are a number of good reports on their EVO systems on other forums I am on.

I'm not much on cat deleting on my street bikes. My new Thruxton R (~700 miles on her now) has plenty of power for me, and I love the subtle exhaust note from the stock system. But I am always interested in smoother throttle response in my FI bikes, and optimal fueling.
 
#33 · (Edited)
I've been reading thru a few of the threads on here about exhausts, cat deletes, piggybacks, etc, and have found no mention of the Rapid Bike modules. Anyone on here have any experience with them?...

...I'm not much on cat deleting on my street bikes. My new Thruxton R (~700 miles on her now) has plenty of power for me, and I love the subtle exhaust note from the stock system. But I am always interested in smoother throttle response in my FI bikes, and optimal fueling.
No, unfortunately not any experience from their systems. But from what I read online about them, it seems like quite a similar piggyback solution as the PCV. Apart from that there isnt possible to use the NB OEM sensors to any meaningful tuning, that must be a misunderstanding or just a sales gimmick.

When I choose from two similar systems, I often find it best to go with the most well known and well supported system just to be able to get and share info. What I and other knows is that the PCV with or without AF-module works as a charm on this bike, with no error message or FI-alarms from the ECU. The AF- module quickly iterate to a reliable fuel table according to our target map. Me and other users is confirming that the setup add smoothness and linear torque to the engine.

Therefor, I have a hard time at the moment to understand the benefits with another and maybe even more expensive system? If a Tuneboy, a TuneECU or another clever solution using the bikes own ECU was available, it would be a different story.
 
#34 ·
13.1 worked on mine. PCV, DNA filter, meerkat cross pipe and meerkat mufflers, desnorkel....but...each cylinder needs individual mapping as the left cylinder required significantly more fuel than the right cylinder to achieve 13.1 AF ratio. So you can't just stick a probe in the muffler. You'll need to make some appropriate bungs to fit o2 probes into each cylinder where the original o2 sensors are fitted when you're tuning on the dyno.

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#39 ·
13.1 worked on mine. PCV, DNA filter, meerkat cross pipe and meerkat mufflers, desnorkel....but...each cylinder needs individual mapping as the left cylinder required significantly more fuel than the right cylinder to achieve 13.1 AF ratio. So you can't just stick a probe in the muffler. You'll need to make some appropriate bungs to fit o2 probes into each cylinder where the original o2 sensors are fitted when you're tuning on the dyno...
Yep, been there, done that and gotten the bike decently tuned with the Autotune module and some proper runs at an old airfield nearby :). I used A/F 13.1 on WOT and down to 13.5 in cruising areas, out of experience that gives quite a descent and pleasant behaviour as well as good mpg. When I read Your thread, I was happy to get the A/F confirmed. Thnx :)

Your graph really shows how nice and smooth the torque is developed through the powerband. Nice job! Am I correct when I remember that You didnt do a base run with a stock setup? Neither did I, as I honestly find the actual numbers quite uninteresting. What a dyno offer is really a good environment for quick tuning and a possibility to investigate the optimum A/F and ignition advance. This, I must guess if I am using the Autotune on the road instead of the dyno.

I am however satisfied for now, with the tuning only based upon readings from cyl#1. On my old Daytona 675, I used Tuneboy and a WBO2 to adjust all three cylinders individually, but it honestly felt like too much job for too small gains. I have kept the OEM bung threads for now and chosen to place the WB sensor in front of the cooler, there is a pic earlier in this thread. Especially as we have no risk of backpressure contaminations from other cylinders on these exhausts, this placment should be really suitable and a tad cooler.

The tune i developed is way leaner than the free ones on Powercommanders site, actually I found it much simpler to use the zero tune with some added ignition advance as my base tune.

I believe You and jsobell both are satisfied with the PCV alternative when it comes to power, so am I and that answers the main question - why bother with another piggyback solution that doesnt offer any extra functions or performance?
 
#35 ·
The power commander maps on their website were far too rich on my bike....causing it to bog down under load. In fact some fuel needs to be taken out to get the maximum torque and a nice flat curve. My dyno guy spent a lot of time on the ignition timing as they are very sensitive to adjustment.

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