Winter Maintenance: Fuel Injectors on a 955i Triumph

 It's been a busy winter and I haven't gotten as much done in the garage as I'd hoped, but breaks in the gloom are beginning to appear so I spent the weekend getting the Tiger sorted and giving plastic welding my first go.

2003 Triumph Tiger 955i Fuel Injector Maintenance

The old Tiger is up at about 90k on the odometer. I did a deep maintenance a couple of winters back (swing arm out, everything gone over from the wheels up) and that seemed to solve most issues, except the fuel injection. These early electronic fuel injection systems in 955i Triumphs is touchy. What I've found that worked is to pull the injectors each winter and deep clean them in the ultrasonic bath, so that's what last weekend was.

Injectors out! I put the end without the electrical connector into the ultrasonic cleaner and give it 10 minutes at 60°C. Once out I clean them up and back in they go. No hesitation or idling problems since.

That vacuum run stepper motor (upper left) is what manages the idle control system - it's touchy! Make sure you've got good vacuum hoses (the black ribbed ones in the pic) and the gasket for the stepper motor is in good shape, or you'll be stalling... a lot. I'm sorting a threaded holder for the fuel injectors here.

Tank off gave me a chance to sort out the airbox, which I now seal with gasket material. At almost 90k, maintenance takes on jobs like rethreading bolts and gasketing tired airboxes to keep everything tight.

Found a stowaway on the airbox under the gas tank. Probably good luck?

Tiger is back together again and ready to take a run at 100k in it's 20th season.

How well did it work? We had a break in the polar vortex (it was -30° last week). In 5°C we went for a blast up and down the nearby river roads and it felt sharp. Doing that bit extra with an older high mileage bike when it comes to maintenance is the key to a happy riding season.

2003 Triumph Tiger 955i Winter Maintenance Continued

Winter Maintenance List:  https://tkmotorcyclediaries.blogspot.com/2020/11/tiger-winter-maintenance-list.html

Front end chassis maintenance:  https://tkmotorcyclediaries.blogspot.com/2020/12/triumph-tiger-955i-fork-reassembly-and.html

Rear end chassis maintenance:  https://tkmotorcyclediaries.blogspot.com/2021/01/triumph-tiger-955i-swingarm-installation.html

Got the backend back together yesterday:

Today it's the rear brake caliper going back on with new HEL brake line, then a brake bleed and if I have some extra time I'll finish up all the hardware bits and pieces on the front and rear and then turn to the engine.

The fuel injectors are coming out and getting ultrasonically cleaned and the rest of the system's getting a flush.

The odds and ends went together well.  Even the brakes were quick to bleed, so with the wheels back on and the new brake lines installed I turned to the fuel injection.

The injectors highlighted in yellow above are press fit in and just pull out of  the throttle body and the fuel rail behind.

The fuel rail is held in by clips and two bolts holding it in place relative to the throttle body.

The whole thing just pops out when you've undone the two bolts.

With the fuel injectors so easy to remove, I'll be quicker at cleaning them in the future.

Ultrasonic cleaners aren't expensive and do a great job on fuel injectors.

Cleaning doesn't take long if you remove the rail and injectors.

Ultrasonic cleaning gets into the small places.

The injectors press fit back into the throttle body with a beefy o-ring to seal them.

My fuel-line replacements for unavailable replacement rubber hoses for the vacuum driven idle control system (on the right) scored a two out of three.  The far one on the left got kinked, so I cut back the hose and I'll see how it does shortened.  If that doesn't work I'll start looking for stronger walled alternatives.

Tiger Brains

The other day I was once again going over the details on the Tiger after taking the tank of for the billionth time.  Even though the stock pipes for the vacuum controlled idle system for the electronic fuel injection hold vacuum when I test them, I can't test that when they're on the bike, so they might be leaking where they join.  I happened to have some fuel line in the right size, so I've taken out the Triumph hoses and put these clear ones on instead to isolate another possible point of failure.

Once I got them in I fired up the TUNEBOY software and figured I'd run the idle control system test since it would move the plunger up and down and with everything off I could check to see that it's all working as it should,  except the ECU wouldn't connect to the computer.  I've done dozens of TUNEBOY adjustments now and know how the bike syncs with the PC over the serial port, but it wasn't connecting.  While trying some variations I turned the ignition on on the bike and the ECU made unfamiliar popping noise, and then none of the dash lights would come on (the running lights still do though).  The ECU no longer clicks off when the ignition is switched off either, which suggests it's not coming on either.

The intermittent nature of this failure always made my ass twitch in terms of it being electronic rather than mechanical.  Mechanical failures tend to be more consistent and easier to diagnose, and I've replaced everything around the idle control system now, so unless Triumph sold me a dickey idle control motor, which seems unlikely since the first one lasted 17 years and did over seventy-six thousand hard, Canadian kilometres and survived seventeen -40°C Canadian winters.  Assuming all the new parts are working as they should, an ECU that was losing the plot is as likely a culprit as anything else I've been chasing, and now it seems to have popped entirely.

So what do you do when your old Triumph's bike brain loses the plot?  Get another, I guess.  Used ones seems to be extraordinarily expensive and look to be in rough shape out of US used parts suppliers on eBay.  And for some reason they're charging twice what European suppliers are for shipping.  With that and the fact that The States seem like they're on the edge of a civil war, I think I'll be looking to the dependable Germans who have COVID19 well managed for a replacement Tiger brain.  If I'm thinking that, I wonder how many other people are avoiding business with the US right now.

But before I go that far, I'm a G.D. computer engineering teacher, so I'm hardly going to let an ECU go in the bin without having a go at it first.  If this is a short or something simple, I can solve that easily enough.  If nothing else I can see how the ECU is set up architecturally, but more often than not I'm able to get electronics I have to open up working again.  Time to flex my soldering prowess.

The most frustrating part about this is that I may well have solved the idle problem with replacement hoses, or maybe I didn't.  Maybe I chased down all of these hoses and parts for nothing and it was the ECU losing the plot all along.  Electronic Fuel Injection (EFI) is a wonderful thing, but the early systems were fragile.  There a lots of posts online about early Triumph EFI headaches, and I've added to them.

Guy Martin does a good special called The Last Flight of the Vulcan Bomber.  They grounded the last of these nuclear bombers in 2015 because they no longer had the expertise and technology too keep them safely air worthy.  In the show Guy talks about why there are plenty of older planes like Spitfires still flying when the Vulcan has to be grounded.  He says the Spitfire was made from bicycle parts you could fabricate in a shed, so they're relatively easy to maintain.  The Vulcan was an industrial machine with early electrical and electronic systems that were many times more complicated.  He goes on to talk about how the Vulcan looked like it came from another planet when only seven years earlier an Avro Lancaster was the state of the art.  There are performance advantages in these leaps forward, but there are also maintenance headaches that mean these early jets will never fly again.

Early fuel injected bikes are a lot like that Vulcan - they can do things earlier bikes can't like get better mileage, not need parts changed to ride at altitude and generally require less maintenance.  I just fixed up one of the last carbureted bikes, a 1997 Honda Fireblade, over the winter.  EFI was around then, but Honda wisely went for highly evolved carburettors rather than new, fragile and poor performing EFI systems.  I rebuilt the carbs, which are a complex but highly evolved four-carb set, and the bike runs like a Swiss (or rather Japanese) watch.  The EFI on the Tiger did the job without any attention for 17 years and seventy-six thousand kilometres including two rides into the Rockies - something no carburetor could do, but when it finally broke, boy did it break.  It's things like this that will make these first generation EFI bikes rare in the future.  Like the Vulcan, they're so complicated and difficult to maintain when they go wrong that they'll get retired from service where an older, simpler bike might still be fixable.



RESOURCES FOR CHASING DOWN ECU PROBLEMS ON A TRIUMPH 955i MOTORBIKE:

https://www.ebay.com/itm/Triumph-Speed-Triple-955-2000-2004-ECU-Steuergerat-CDI-S1000T3/324154967093?hash=item4b79244435:g:BCEAAOSwZrteryUL

There are early Triumph EFI issues aplenty online:
https://www.triumphrat.net/threads/ecu-repair-refurbishing.525873/
https://www.triumphrat.net/threads/bad-ecu-on-my-2006-speed-triple.159082/
https://www.triumphrat.net/threads/955i-idle-hesitation-porblem.971699/#post-2004081361
https://www.triumphrat.net/threads/ecu-unit.80778/
https://www.thetriumphforum.com/threads/s1000t3-ecu.22000/
https://www.triumphrat.net/threads/1999-955i-ecu-needed.93566/#post-1107942

Used Parts, not of the vintage I'm looking for though:
http://www.rubbersideup.com/triumph/tiger?p=2

https://www.bikebandit.com/oem-parts/detail/triumph/t1291000/b1389042?m=121594&sch=565828
Wahay!  A new ECU is two-grand, AMERICAN!  That's over $2500 Canadian!  The whole bike cost me three grand.  See what I mean about the costs of keeping emerging, fragile old tech active?

Then vs. Now

I've been wondering why motorbikes don't seem to have moved on in the way that cars have.  To that end I'm trying to find comparisons between 1960s (pre-oil crisis) vehicles and current vehicles.  In trying to keep apples with apples and find stats for similar vehicles.  The problem is a 1960s Cooper Mini doesn't have anything like the crash worthiness of a new Mini Cooper, and that crash worthiness costs weight, though not as much as you might think.  The real cost in weight is our expectations around size.  The new mini is significantly larger mainly because minimalist, small cars don't sell.

Our improvements in engineering efficiency are often overshadowed by our need for bigger, more plush vehicles.  My thinking is that this shouldn't be such an issue on a motorbike, it's not like our bikes have gotten much bigger in the way that cars have turned into SUVs.

An example, the Mini Cooper.  The new car has nothing mechanical whatsoever to do with the old one.  Other than the name and marketing niche, these cars are very much creatures of their times.

length	3,054 mm (120.2 in) (saloon)
Width	1,397 mm (55.0 in)
Height	1,346 mm (53.0 in)
Kerb weight Horsepower Fuel Economy	617–686 kg (1,360–1,512 lb) 1275cc / 78hp (16.35cc/hp) 6l /100kms

via wikipedia

Dimensions (LxWxH): 3723 / 1683 / 1407 mm
Kerb weight: 1150kg - 1185kg
Fuel Economy: 6.1 l/100kms
Horsepower:  1600cc / 121hp  (13.22cc/hp)
So the new car is:
18% longer, 17% wider, 4% lower
46% heavier all with the same mileage!
                                       courtesy of Mini.

So what you've got is a much bigger car that offers all the modern amenities in addition to more space that gets about the same mileage, and it does it with an engine a third larger than the old one.  Put another way, the new Mini is about twice as efficient as the old one (it uses the same amount of fuel to move almost twice as much car).  On top of that Mini needs three less cc to get a horsepower out of an engine.  It isn't much, but it's an improvement, unlike the bike below.

1969 Honda CB750

Dimensions Wheelbase	L 85 in (2,200 mm) W 35 in (890 mm) H 44 in (1,100 mm) 1460mm
Seat height	31 in (790 mm)
Weight	218 kg (481 lb) [1] (dry) 491 lb (223 kg) (wet)
Fuel capacity	19 L (4.2 imp gal; 5.0 US gal) [1]
Fuel consumption Horsepower	34.3 mpg-US (6.86 L/100 km; 41.2 mpg-imp) 68hp  (10.82cc / hp)

via wikipedia

Here is Honda's modern ode to the CB750:
The Honda CB1100A
Dimensions: 1490mm wheelbase
Weight:        248kgs  547lbs - wet
Mileage:       41mpg
Horsepower: 82.5 hp (13.8cc /hp)

At 1140cc, the new Honda is 390ccs larger, though follows the same engine layout as the old CB750.  They are within 3 cms of each other as far as wheelbase goes - bikes aren't significantly physically bigger in the way that four wheeled vehicles have put on weight in the past forty years, though cars seem to have done it while finding ways to get way more out of each litre of gas.   That new mini is a much bigger vehicle, almost twice the size of the original in terms of mass.  Bikes haven't grown anything like that, yet their mileage is pretty much the same.  

Keep in mind we were comparing a twelve hundred cc 1969 Mini with a 1.6l modern Mini, a 25% increase in displacement.   The new CB1100 has 33% more displacement on a heavier bike and gets the same mileage as the old carbureted one.  Why is the new bike so much heavier?  It's not like a car - it isn't larger than the old bike, it isn't carrying airbags and all sorts of other modern safety gear other than ABS.  To top it all off a carburetated 1969 CB750 used to use 10.82ccs to make a horsepower, the new one uses 13.8ccs to make a horsepower.  A lot of that could be tuning the engine for more torque, but here we are, 45 years later using more displacement to make less power?  What the hell is the point of fuel injection?

In 45 years of material development, the new Honda is 56lbs heavier.  The 1969 CB750 is within point one of a mile per gallon of the 2014 CB1100.  You might say it's not a fair comparison because they're not both 750cc bikes.  Honda's only current ~750cc bike is the NC750x, which is a parallel twin rather than a four cylinder.  Even with that disparity the NC750x tips the scales at 483lbs, still 2 pounds more than the 1960's 750 four cylinder.  And it's not like Honda isn't an engineering powerhouse.

If you say the motorbike vs. car argument isn't fair, how about motorbikes to bicycles?  A Tour de France bike in the 1960s weighed about 22lbs.   Modern bikes are limited to 15lbs, though in 2004 Armstrong had a 14.5 lb bike and without the limit a 10lb bike is more than possible.  If bicycles have dropped 30% of their mass in the last 45 years, why not motorbikes?

If we look at this from an automotive/bicycle equivalent efficiency angle, the new Honda CB750 should have a 20% more efficient engine and weigh 30% less.  The 2014 CB750 happy memories bike should get about 80mpg, weigh 344lbs and produce about 82hp.  This bike would have a power to weight ratio of about 4.2lbs per horsepower, approaching what some of the fastest sports bikes in the world have.  The sensible choice then would be to make the bike a 650cc CB throwback, which still produces a  better power to weight ratio than the CB1100 and weigh even less with the smaller engine.

I asked before and I'll ask again, why haven't bikes advanced at the same rate as cars (or bicycles)? Why isn't the new ode to the CB750 a CB650cc bike that produces more power, uses less gas and rides far better than its prehistoric inspiration?  Motorbikes are stripped down, simple machines, in many ways still very similar to the machines made decades ago.  With that in mind, why don't we see the radical evolution in technology evidenced in the Mini and in racing bicycles in the past 45 years in the Honda CB750/CB1100?  If we aren't larding up bikes into SUVs (though some people are), the efficient burning of gasoline should have produced astonishingly high mileage numbers by now.  Where is the direct injection? Where are the intelligent drivetrains and engine management systems that have produced cars that weigh twice as much and still burn the same amount of fuel?  Where is my frictionless magnetic drivetrain with integrated brakes?  Where is my kers?


With an integrated kers system, I could be riding a 400cc bike that when the kers kicks in feels like a 1000cc bike, then recharges while I ride.  I could pull onto the highway or overtake on a super light bike that can feel like a one litre rocket when I need it and sip fuel like a 400cc machine when I don't.

Zero Motorcycles: all electric, but I don't know that we
have to go to that extreme yet, we're not exploring
internal combustion that well.

Because motorbikes are small and inherently efficient compared to cars, manufacturers haven't pushed engineering limits in the way that they have with other vehicles.  I'm looking for the future of motorbiking, and it doesn't feel like manufacturers are testing limits in a way that makes my choices feel any different than they were a decade ago, let alone four.

Discontinued Tigers and Triumph Supporting its Riders

If you follow the blog you'll know I'm on a mission to get my 2003 Triumph Tiger 955i to roll over into six figures on the odometer. I picked up the bike with under forty-K on it and have done the majority of the now high miles on it. Over that time I've had an ongoing battle with the early fuel injection on the bike, but other than that it has been my preferred ride even as a series of other bikes passed through the garage.

Once again the fueling has gone off on the bike just as I was hoping to push it over the 100k mark in its 20th year on the road. If I lived somewhere where the weather wasn't trying to kill me for four months of each year this would be an easier goal, but trying to do it in Canada where the bike has to sit through minus forty winters and then navigate the frost heaved results in our too-short riding season? It's technical a flex I'm up for, but it's a shame that Triumph isn't.

I tried the usual solution of rebalancing the fuel injectors, but the bike is still stalling out and running rough. I checked the valves less than 15k ago so that isn't likely it. If it isn't throttle body balancing, which the bike is prone to needing, perhaps it's time to, at over 90k, to finally replace the o-rings and gaskets in the fuel injection system, but Triumph tells me that the majority of these parts are discontinued.

One of the reasons I enjoy the old Tiger is that it still catches eyes and prompts conversation when I'm out and about. Another reason I like it is that it can pretty much do anything (I've trail ridden on it and done multi-thousand mile two-up road trips too). It fits me better than anything I've ridden, is fun to chuck around in corners and has handled axle deep mud when I needed it to. The engine is full of character and pulls well even two up and, considering the miles it has done, the amount of TLC needed isn't unreasonable. I'd love to keep this bike going indefinitely, it's a shame that Triumph don't feel the same way.

I had a chat with the dealer (who isn't particularly local, it's a 170 mile round trip to go there physically - I usually get parts delivered), and they said that this is a problem with Triumph - they don't support their older machines. He then went on to say I couldn't use generic o-rings because the Triumph parts are strangely size specific. I'm going to try anyway because I really want to be able to jump on my old Tiger and ride.

Suzuki runs a successful vintage parts program so I'm not sure why Triumph wouldn't want to do the same to keep their bikes on the road, especially when they lean on brand heritage marketing so much.

Here's Nick Bloor's take on it:

Never standing still, always pushing to get the best from ourselves, for our riders. Building iconic motorcycles that celebrate our past while embracing the future through bold design, original styling, purposeful engineering and a genuine passion for the ride.
Always focused on delivering complete riding experience, creating bikes with the perfect balance of power, handling and style that totally involve the rider and bring out the best in them. 
This is our passion and our obsession. 
We are chasing the same thing as our riders THE PERFECT RIDE.
Nick Bloor
CEO Triumph Motorcycles

All good stuff, but maybe focus a bit more on celebrating Triumph's past, Nick? That includes the bikes your reborn Triumph have been making since the nineties. For some of us you created that perfect ride a while back.

When you market on brand history and provenance, shouldn't you support brand history and provenance? I'm coming at this hard because I want to believe... and keep my (not so) old Triumph rolling.

Tiger Success (!) and first ride of 2025

 Last fall I took the fuel injection apart on the 2003 Triumph Tiger 955i. It wasn't fueling properly and was unrideable. I barely got any mileage on it last season, so I replaced every o-ring in the system and got a new fuel pump for it. It also got new throttle and clutch cables last year. If this last hail Mary attempt to resolve the atrocious fuel injection on this old bike didn't work, it was out the door.

The good news is it fuels nicely again for the first time in a year! I've still got to tune it and get the idle right, but it feels fantastic. Look back over the posts in December and earlier to see the details and where to get parts. If you're trying to keep an old Triumph 955i on the road (Triumph doesn't support them with parts any more), try this, it seems to work!

Battery needed a kick, but once charged up it ran like a top.

The clawed hands of winter still twist into the sky.

First chance to try out a new Shark helmet. My first and I'm not disappointed.

Still got snow on the borders.

The Grand River is swollen by the spring runoff - that's the camp ground underwater on the other side.

That grin is involuntary. The first time you lean into a corner after a long winter on four wheels is magical.

Amy knows how it feels...

Nice to have one road worthy. The C14 valve job continues when I have time, but work has picked up and I'm travelling again, so my weekends are seldom my own.

Here is the radiator loosened so I could get to the front cam sensor to change the o-ring. The Murph's Kit came with an oversized one. That was 40 minutes of sweat and swearing before I gave up and stepped away (again). This was a giant time suck at a time when I don't have a lot of... time.