Finding Your Way Around OEM's Giving Up on Parts Support: Triumph 955i Fuel Injection Seals

With Triumph giving up on my Tiger before I'm prepared to, I'm going to document the research and give details on what works when you're trying to keep a Triumph 955i's fuel system working by replacing old o-rings.

This has involved a crash course in o-rings and engine operating temperatures. As I work out a fix here I'll post details on o-ring sizing, what type works and include data on measuring the intake manifold at temperature.

It's been all Concours for the past few weeks while the Tiger is laid up. I'm hoping to get the fuel system sorted before the snows fly and I have to wait for next year.

Here are the measurements for the upper and lower fuel injector seals. The classy move by Triumph would be to open source publish the technical details for all the parts they no longer support so that the rest of us can get on with keeping the history of the marquee alive. With that in mind, here are the deets for the upper and lower fuel injector o-rings:

The thick ones go on top where the fuel injector meets the rail. My best guess is 3mm thick by 1.5cm outer circumference.

The skinny ones go on the bottom where the fuel injector slides into the intake manifold.

My best guess there is 2mm wide by 1.4mm outer circumference. 

Unfortunately, buying off the shelf boxes of o-rings isn't likely to get you anything that fits. The two below from Amazon didn't. This thing looks handy: https://www.allorings.com/O-Ring-AS568-Standard-Size-Chart.

The Tiger is a metric bike, so I'll work in mm (if Triumph went imperial on o-ring, what the actual f***). The thicker o-ring is 1.5cm or 15mm outside diameter (OD) and (I think) about 3.5mm cross section (CS). Looking at that chart, the #203 is a 14.58mm outer diameter with a 3.53mm cross section. That makes it mighty close. What would be nicer would be if Triumph just came out and gave us the precise sizes for these parts it has discontinued. Triumph?

The thinner one is also a 1.5 (ish) mm outer diameter (15mm-ish), but the cross section is thinner - perhaps two and a bit mm, and they have a 2.62mm cross section standard o-ring size. You'd have to hope Triumph didn't make bespoke o-rings for their fuel injectors, right? For the skinny o-ring I think I'd take a swing at the 2.62mm cross section / 14.43mm (1.443cm) size.

The All O-Rings site also has a good description of the materials you want to get your o-rings in. Nitrile and Viton are what I went with in the pointless Amazon order, but those are the materials you want in a fuel heavy application like this.

That's the configurator (right) - pretty straightforward, but it sounds like they manufacture each order, which probably won't make this a viable solution for someone just trying to keep their old Triumph on the road.

If only there was some kind of network of retailers who supported Triumph motorcycles who could order this parts to help their customers keep their older Triumphs rolling... some kind of 'dealer' network who understand how parts work and how to order this sort of thing in large enough quantities to make a profit while offering customers what they need.

RESOURCES

How hot motorcycle engines runs: https://blog.amsoil.com/extreme-heat-is-hard-on-your-motorcycle/

Buna (Nitrile or NBR) o-rings: https://sealingdevices.com/o-rings/buna-n-o-rings/

Viton vs. Nitrile o-rings: https://www.nes-ips.com/viton-vs-nitrile-o-rings/

All O-Rings https://www.allorings.com/

They have sizing tools! https://www.allorings.com/o-ring-kits-and-accessories/o-ring-sizing-tools

I'd prefer to use All O-Rings for the parts, but they might be a B2B type of thing, and I'm not a B.

Amazon's kits:

Turns out Amazon's shot-in-the-dark kits didn't work either. There's more to this o-ring sizing caper to come. I wish I could just 3d print the nitrile o-rings I was looking for (doesn't look like it's additive manufacturing friendly).

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.

Fall Moto Photos

 Alas, the Tiger's fuel system is acting up (again), so it's all Concours14 this fall, but the big bike is doing the job. It handles two up without breaking a sweat and when I want to ride it like a sports bike, it never misses a beat. It's heavy, but once it's in motion it seems to loose one hundred pounds. It's no Fireblade, but it's surprisingly willing in the (few) twisties we have around here.

This time of year the fall colours mean you can enjoy a ride even on our tediously straight roads...