Sorry mate, but while I like some mods on a bike, I don't agree with the saying that the 9er (or any other bike/car) is a mess that requires expensive or complicazted mods/additional devices or the need for a mechanical engineer to work properly.
The ignition timing change in 2-3 gears actually existed on the 4TX, using the gear position sensor but I have no factory info about the 9er. Changing the ignition advance is something I don't advice to play with, because it may be the best way for a disaster : engine overheating, valve failure, etc.
The fuel injection cut during rev-down is something that is present on all injected engines, not only the 9er. Why would a four-strokes engine need fuel during rev-down ? It only increases fuel consumption & pollution. Fuel cut-off is an improvement over carbs, not a problem at all, even on the 9er, unless the idle rev speed is way too low, and the gap between the idle-rev & the cut-off rev limit - 2000rpm - is too big. Or the wrong gear is in use.
And no, not all carbs will deliver a small amount of fuel during cut-off, some of them had an improved design to cut fuel during rev-down - eg on the SR500 which was not a very sophisticated bike even with its above-average carb.
Standard carbs will deliver some fuel during rev-down because they were designed to be cheap, during an era when fuel was not expensive and without exhaust gas regulation. This was not a researched design, this was a design flaw.
Off course there is always the case of a badly tuned engine, or a rider who don't have all the skills to master a big twin or think it works like a four cylinders and uses too much low revs, but all in all, the 9er is a good bike with a good engine. As I said above, the main problem comes when the oem cans are replaced with aftermarket ones, which are designed to make noise & money, but are not designed to work with an injected engine.
I didn't write that the 9er is a mess
I like the 9er in standard form, I prefer better it when the emissions and behaviour control (retarded timing) are negated..
i think I've proven to anyone's satisfaction, if not just my own, that advancing the timing on the 9er is not problematic at all, and when I changed the cam chain and did a service recently the spark plug colour could not have been more normal (That is with the Samios remap, with advanced timing tables and fueling changes) . Other people who have advanced the timing on the 9er or 850 didn't have problems. It is a standard modification for nearly every bike designed to run on the lowest quality fuel, which I'm pleased to say we don't ever get in the UK (Here's a list of 4 degree advancers on ebay as an example of their widespread use https://www.ebay.co....dvance&_sacat=0) If people were having serious issues I'm sure we would hear about it.
I was comparing the carb behaviour to an 850, having had all version of TDM I can appreciate the differences in behaviour. The 4tx is very easy to balance the throttle mid corner with, the 900 not so much. The difference is the instant fuel shutoff on the 9er, and the fact that it doesn't restore fuel supply until the revs are very low in comparison to other FI bikes. For example the K100 I had restored fuel at around 1900rpm on overrun. The TDM holds the fuel off for much longer, I think actually to below 1600rpm, which might be why raising your idle speed to 1500 really helps there.
I'm not sure about your last comment about silencers not being designed to work with an FI engine. To me they are designed to flow gas while reducing sound output levels. I understand the concepts of the requirement for some backpressure and the importance of maintaining high exit velocity to encourage exhaust gas scavenging, but I'm not sure I understand how an exhaust pipe design can be changed to suit an FI engine differently to a carb fed one.
The reason i didn't buy an expensive PC and then pay someone to play on a dyno frigging the map to try to hide perceived errors in fueling, is because a lot of the problem with rideability I have experienced didn't feel completely like fueling.
I think i mentioned in another thread I'm on the lookout for a bike with the Yamaha 660/650cc single (a few bikes use it) and I've already lined up a tuner to remap the ECU for the same reasons. If I bought a 650 single which had a PC, I would recover some of the ECU remap costs by selling the PC.
Yamaha have a similar set of circumstances with their 660single, in the XT660 and MT-03 etc.... A lot of people find them an all or nothing ride with jerkiness around town at low revs. Aprilia put the same engine in the Pegaso 650 and remapped the ECU to produce a much more refined, smooth, and enjoyable ride. The main difference documented between the two ECU programs is that the Pegaso has has a lot more time spent on the ignition table. At some point Aprilia changed the tables again and then the reviews of the bike was that there was a surging at around 3000rpm. An examination revealed that the ignition timing tables had been changed to be more like Yamaha's. The Yamaha ignition map is more retarded below 3000rpm. The problem is that due to the choice of gearing 3000rpm is in the cruise zone for top gear in light traffic......
From one of the tuners sites about this...
The re-flash offer:
New fuel tables
New ignition timing tables (That will cure the surging 100% and that is the main problem of this ecu no matter what the O2 eliminator’s manufacture says)
New rev limiter at 7850 rpm
Disable deceleration fuel cut for perfect throttle response
Later TDM900 ECU's have a smoother low speed behaviour, and I suspect that when examined, the ignition tables will be considerably smoother too.
Like I said earlier, I'm not criticising the 900 and it would be silly of me to do it now, given that I've owned and enjoyed it for longer than any other bike I've ever owned, but the remap of the ECU isn't offered as a service just for you to say you have found someone who can make your bike drink more fuel. The behaviour of the bike, in particular being able to feather the throttle mid corner without any on-off lurching is great, especially if you're riding in a group and get (quite incorrectly and in a very amateurish way) bunched up together ( expecting a comment about learning to pick the perfect entry speed here )
So that was my reason for the remap of the ECU, not so much because the bike is bad, per se, (because as you have said about bikes and has been correct about cars since early Bosch FI systems I used to work on , they all cut fuel). But that isn't ideal for me. The ignition tables are sometimes awry, and not ideal for me, so I get someone who knows what they're doing to change them for me. And the torque reduction in low gears is standard on many bikes and I don't like it, so again, i got someone to remove it for me.
I see this sort of thing as being no different to changing the colour of the bike (didn't Yamaha produce the right colour ?) or changing tyres, or suspension (didn't Yamaha make it perfect in the first place ? ) The answers to the questions have nothing to do with it being a good bike or not, but more to do with how I want my riding experience to be
So comparing an ECU remap to a Power Commander, I find the costs to be comparable to one another and I find the extra benefits of the ECU remap, in terms of having the ignition timing changes outlined above, outweigh the retuneable nature of a PC....... For me.......
Ultimately I think the decisions made at the factory about how a bike should feel when ridden are a compromise between what the test riders suggest, and what the marketing people need to deliver., as well as any legal obligations which need to be met.......and like every compromise they cannot suit everyone
EDIT, I just found this out about the Yamaha 660's, maybe Yamaha did a similar thing with the later 900's ?
I have learned of some new functions between the 01 & 11 ECU on the dyno. Yamaha have removed the over run shut off function on the 11 ECU.
What this means is when you are riding on the freeway & shut off the throttle the 00 & 01 ECU cuts off the fuelling completely, the 11 ECU does not cut the fuelling any more, it leans the A/F ratio out . This feature offers a smoother uptake of the throttle when you open the throttle again.
Edited by fixitsan, 31 July 2018 - 12:31 pm.