ST1300 Fuel Injection

MeiSTer

Joined
Apr 20, 2006
Messages
40
Location
MA
I'm sure you guys must have discussed this before so excuse me for bringing this up once again. It seems out of character for Honda to release a product that is so well designed in so many other areas and yet fail to finish it off with smooth fuel flow and drivability at low speed.

I've owned 9 Honda products including Accords, Preludes, Civics, Acuras, and a VF750. Some carburated and some fuel injected. All exhibited predictable and linear fuel delivery. I realize that it is difficult to map smooth fuel flow through a wide power band under a wide range of operating conditions and many manufacturers screw it up, but certainly a company with Honda's rich racing heritage and advanced engineering prowess is certainly capable of doing better. Expecially considering that an aftermarket company is able to correct the problem with a $99 part.

Did they consider the twitchy behavior to be a feature perhaps? Maybe a way to make the bike feel quicker or more responsive?

Don't get me wrong I love the machine and will get one of those $99 parts, but the oversite is perplexing to me.
 
Let's fix it

Now for a more useful reply to the mans posting. I share your criticism of the low speed snatch (I never have been PC anyway). I installed the TC FPR and it helps, enough to justify me keeping the bike, but only just. A complete solution to the EFI induced snatch and lurch is a potential gold mine to some smart guy who engineers a fix and sells it. ST1300 owners would eagerly pay $100 (IMHO) to improve this pesky twitch on what is a superb machine. Has anyone thought of designing a larger cable wheel for the throttle body? This would result in a differential ratio between the throttle grip and the butterfly valve shaft. Currently this ratio is 1:1, say it was 1.1: 1, the throttle grip would need to be twisted a little bit more to reach full throttle but a low speeds it would be tamer.
 
Honda gets a lot of criticism on this board and others. The '06 tool kit comes to mind right away :p: Where the PC part comes in is when people simply blurt out broad brush statements that they use to try and characterize everyone's ST. And that's where toe stepping happens.

Heat is an issue for some, but not for others. Wind buffeting and shields are a problem for some, but not for others. Throttle sensitivity is a problem for some, but not for others. If these things were manufacturing or engineering defects, we'd all have issues with them. But not everyone does. In fact, it would seem that it's the minority that suffer from these frustrating problems. For example, I personally don't have an issue with the throttle -- it took me a few months to get used to the sensitivity of it, but now I like that level of control.

The members here are generally very helpful. More than most boards, the majority here seem to try and post with the Golden Rule in mind. But generalized statements used to try and characterize all ST's don't fly well.

Tiny said:
The FPR helps but it is still an issue. It is not deemed PC on this board to criticize momma honda.
"It is your imagination that the throttle is not perfect....it is your imagination that the throttle is not perfect....there is no heat issue....there is no heat issue....it is your imagination..........................."
Click to expand...
 
Ken said:
Honda gets a lot of criticism on this board and others. The '06 tool kit comes to mind right away :p: Where the PC part comes in is when people simply blurt out broad brush statements that they use to try and characterize everyone's ST. And that's where toe stepping happens.

Heat is an issue for some, but not for others. Wind buffeting and shields are a problem for some, but not for others. Throttle sensitivity is a problem for some, but not for others. If these things were manufacturing or engineering defects, we'd all have issues with them. But not everyone does. In fact, it would seem that it's the minority that suffer from these frustrating problems. For example, I personally don't have an issue with the throttle -- it took me a few months to get used to the sensitivity of it, but now I like that level of control.

The members here are generally very helpful. More than most boards, the majority here seem to try and post with the Golden Rule in mind. But generalized statements used to try and characterize all ST's don't fly well.
Click to expand...

Very well said Ken... You've hit the nail on the head :)

Regards,
 
I apologize if the phrasing of my post was taken as a criticism of Honda. My bad. My intention was not to criticize but spark discussion and gain a little insite from those with greater experience than I. Certainly no company is perfect but I'm one of those that believes Honda is probably closer to achieving that goal than most. Obviously, I continue to invest heavily in the company and will continue to do so (product and stock). Having said all that, a little constructive criticism can be beneficial...

My thinking was that a company as technically savy as Honda must have designed the throttle system on the ST to operate as it does and that it is expected behavior. Not having ridden other fuel injected bikes I have nothing to compare it with. I have read about numerous issues with fuel injection on other bikes in trade publications however. Enough to know that it can be problematic.

I was wondering what it takes to achieve smoother operation. Is it a matter of refining the injection software map, increasing or decreasing the fuel pressure, changing the throttle cam, or a combination of all of the above.

For me the snatch does exist and I find it is possible to work around and through it, but it takes effort and on long rides can become tedious, especially with a passenger. Maybe it is more pronounced to me since I have never experienced it and am just not used to it.
 
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Read a very interesting article at the weekend on this subject. I'll scan it sometime and post a copy. Apparently it's all to do with emission regulations and it's only going to get worse. The article explained how catalytic converters can do no more to minimise pollutants and so vehicle manufacturers are having to design engines to run leaner. As the regulations (worldwide) get tightened more and more, one of the ways to meet them is for the manufacturers to force the engines to run extremely lean on tick over when no power is required. The down side of this is that the transition from no throttle to open throttle becomes very abrupt. Like I say, this situation is only going to get worse over the coming years. A number of bikes will disappear from the showrooms (at least in Europe) at the end of this year as the manufacturers are completely unable to make them meet new regulations for 2007. One thing the article stresses is that bikes with brand new engines, built from the ground up for the regs are much better at dealing with this than modified older designs. As manufacturers have been moving in this direction for the last 10 years or so, I suspect this is part of the reason it shows on the ST. The fact that a higher pressure fuel regulator appears to solve the problem for some would seem to back this.

For my own take on it, at first I found it quite frustrating, but as I have become familiar with the ST it has become less and less of a problem. It does still occasionally catch me out, but not to the extent where I feel the need to do anything about it... other than ride more :D

Regards,
 
Dave,

Thank's for the reply. I hadn't considered the emission problem. I would be very interested in reading the article.
 
I have read verious reviews and all FI bikes are a bit twitchy and the Hondas were generally deemed the most twitchy. I will let others specualte on a exact reasons and intentions. One thing to remember is that car FI engines are twitchy as well The power to weight ratio is nowhere near the bike. Plus you might have an automatic and thus a torque converter. The same holds true with regards to driveline lash. A friends Suzuki Sidekick (small 4x4 SUV and manual trans) lurches in first and some in second gear when going on/off throttle. You don't notice it so much in the higher gears since there is less torque multiplication in the tranny.

I like you wish the manufactures would spend some more time, and therefore money, in trying to polish the edges more but they just do not. It seems that once in development and the vehicle is to the point they think it will hit their sales targets, they close the book and look to the next thing.
 
It's only a shorty, but interesting all the same on this topic. Obviously this is specific about 2006 bikes, but as Honda have been messing about with emissions for years, I feel it may be related in some way to what we experience.

Regards,
 

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The oversight perplexed me as well, but for $100.00 and some minor moaning, my problem got fixed with the FPR.

Honda is not perfect. Recalls happen, dealers are "hit and miss", heat issues, 13k for a touring bike-- wiring harness is extra :confused:

But there are pros. Bike is designed very well, tip over wings, good power, good braking- ABS, good warranty, price, etc.

I think it boils down to having a realisitc perspective and having patience.


--Bryan
04ST1300A
STOC# 5197
:04biker:
 
g17 said:
I think it has to do with more than emissions, e.g your first impression was correct (poor fuel delivery for such a refined machine). I read an article recently discussing when bikes began switching to fuel injection and they stated that Honda has never been as smooth as the other manufacturers in fuel delivery. Go to motorcycle.com and motorcycledaily.com and do some reading on bike comparisons starting around 2000 and just about every article will indicate that Honda's FI delivery is not as smooth as the other bikes compared. My 06 Kawasaki doesn't suffer from the abrupt jerkiness associated with the ST1300. It jerks alright, but only when you want it to. BTW, if the PC crowd doesn't like your opinion, F*** em!:eek:
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Honda ST1300 meets CARB 2008 standards. I wonder, when we get a chance to ride other manufacturer's 2008 models if they will be jerky on and off throttle also. FPR solves some of the driveablity. But I'll bet it won't pass CARB 2008. Generally speaking the worse something drives the happier the Fed's are with it.
 
Burger said:
It's only a shorty, but interesting all the same on this topic. Obviously this is specific about 2006 bikes, but as Honda have been messing about with emissions for years, I feel it may be related in some way to what we experience.

Regards,
Click to expand...

I agree, I think it is what we are experiencing. I have an 06 and I wonder if there are any differences in the ECU software from year to year.

I read in another thread that someone had farkled the FPR and Staintunes and said that it made a dramatic improvement. Based on the information in the article about the lambda sensor the difference in fuel pressure and less restrictive exhaust must somehow cause the FI computer to alter or select a different fuel delivery map. Maybe fake it out, since unburnt gases don't cause the ECU to lean out the mixture as much at closed throttle.
 
Burger said:
It's only a shorty, but interesting all the same on this topic. Obviously this is specific about 2006 bikes, but as Honda have been messing about with emissions for years, I feel it may be related in some way to what we experience.

Regards,
Click to expand...

Dave,
I read this is Ride magazine this week too. It sounds like there are some bikes a lot worse affected than the ST too. Fazer 1000? or was it the FZ1, I can't remember, and I've binned the mag. Apparently it's absolutely horrendous.
The bikes with the electronically activated secondary throttle butterflies seem to cope with the lean burn OK, but guess what the guys on the ZX14 forums are doing? Removing or altering the secondary butterflies to get full power at low revs, along with snatchy delivery. Luvly.
It seems the perfect solution would be to have a Power Commander with a fuel map set up to give perfect RIDING mixture, not perfect EMISSION mixture. I think the FPR does this but it's not a technically elegant solution.
Anyway, how would all worldwide new bike emissions being set up for rideability stack up against a handful of jumbo jet takeoffs?
This sort of thing really bugs me.
And another thing - why did my old carbed ZX11 with 140ish BHP give me 50+mpg and my lower powered ST can't? And my fuel injected ZX12 does about 28mpg which I find unbelievable.

OK, rant over.:)
 
FWIW, according to the 2006 Honda Parts Catalogue, the EFI unit has not changed since the bike's introduction. There are different EFIs for the North American, European and French markets, but these have remained the same within each market.

Ciao,
 
Isn't this likely to be more related to the programming of the EFI's rather than the EFI's themselves?
 
Don't think so. If Honda had changed the software used by the EFI, it would probably be pre-loaded on all replacement units, and this change would be reflected in a slightly different part number. I stand to be corrected on this matter, however, if anyone knows differently...

Ciao,
 
I take it by EFI's you mean the injectors? I would have thought they'd be controlled by the ECM rather than having any independent programming. Manufacturers often change the ECM programme without changing the part number of the ECM. Replacement units would be sold unprogrammed for the dealer to install the latest software release. I don't know this is how Honda work, but I do know it's how many car manufacturers do.

Regards,
 
Relevance to a french spec bike...?

Interesting stuff gents. I'm currently considering getting one of TurboCity Toms FPRs for my french spec ST1300A ('04). My main concern is that I'll not get the promised improvements since somewhere in the past in the tech forum I read that the way the french spec bikes are 100bhp limited is via specific injectors and ECUs.
The question is... does someone have an 'international' parts catalogue (the only one I've been able to download is only for US models) that I can check to see if it is really both ECU and injectors that are french specific or just one or the other? If it's the ECU only and not the injectors I have high confidence that a new FPR will improve driveability. However, if the injectors are also french specific (as has been hinted in the past) then I may not get the full improvement in driveability that I've read so much about (and so not get my full $100 worth!)

By the way, I've already emailed TurboCity Tom and he doesn't know of anyone that has fitted the FPR to a french spec bikes.

:shrug2:

Regards,

Mark Galle
...British, based in Toulouse, South of France
 
Clarification: what I was calling the "EFI" is actually called the "PGM-FI" unit by Honda in the Parts Catalogue, and the "ECM" in the Workshop Manual: it is the electronic control box for the fuel injection system. There is nothing about programming it in the Parts Catalogue or in the Workshop Manual, so if you ordered one from a Honda dealer, they might download something to it before selling it to you, but I wouldn't think so. If the average Honda motorcycle dealer is supposed to set it up, the maps would be "out there" and I've never heard of anyone updating their Honda PGM-FI. But I'm just speculating...

As mentioned above, I have the ROW Parts Catalogue, and according to its hallowed pages, the injectors are identical for ALL ST1300s. Indeed, the entire throttle body assembly is identical throughout the world, apart from the North American bikes.... Cams are the same, too. Different ECM/PGM-FI for France, however.

Ciao,
 
They should make the California bikes meet CARB2008 and leave the rest of them alone.
 
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