Triumph 955i fuel injector O-ring research

Tiger's still not working (see previous post). Here's my best guess: the new fuel pump has caused the old O-rings in the fuel line to leak causing a vacuum leak, so I'm digging for new O-rings, but of course Triumph doesn't sell them anymore and seems to go out of their way to not tell you what size they are. Wouldn't it be nice if a manufacture who don't support their bikes after only 20 years at least open sourced the specs so the aftermarket could pick them up?

Anyway, off to the internet I go to research! Here are the notes:

https://www.thetriumphforum.com/threads/triumph-2003-955i-cutting-out-when-throttle-blipped.27324/page-3

"There is a O ring on the Tps (throttle position sensor) that gets worn and swells causing a voltage delay when closing the throttle causing the incorrect signal to the ECU.

Cure? Simply remove this O ring haha, So i did this last night and took her for a test ride this morning whilst picking up some essentials. BINGO!"

Part 23 = T3600053 | O ring
Part 4 = Throttle potentiometer Part Number: T1290500 - but it doesn't look like it has an o-ring involved in it, so that advice is suspect.

12 = O ring. Rail, Part Number: T360005313 = O Ring, Injector, Upper Part Number: T1245016
14 = O Ring, Injector, Lower Part Number: T1240806

Store: The O-Ring Store https://www.theoringstore.com/store/

Parts: V3.00x008 V75 (upper), and V2.40x009.6 (lower) - those are the dimensions (upper = 3

Suggestions from forums on potential issues: "Don't be surprised if you find that the end of your fuel line is actually cracking at the fitting. I chased O rings for a while and discovered that to be my source instead."

"the union (which is plastic) was the culprit. It was cracked and just giving it a wee jiggle made it worse"https://www.triumphrat.net/threads/955-sprint-fuel-o-ring-rubber-sizes.163915/
Fuel Fitting O-Rings

* Triumph O RING, FUEL PIPE CONNECTOR - T1240181
* Buna-N O-Rings - #9452K19 McMaster-Carr https://www.mcmaster.com/

o SPECS
+ AS568A Dash Number: 010
+ Type: O-Ring
+ O-Ring Type: Standard
+ Width: 1/16"
+ Actual Width: .070"
+ Inside Diameter: 5/16"
+ Actual Inside Diameter: .301"
+ Outside Diameter: 7/16"
+ Actual Outside Diameter: .441"
+ Material: Buna-N
+ Durometer: Hard
+ Durometer Shore: Shore A: 70
+ Temperature Range: -35° to +250°F
+ Color: Black
* Viton O-Rings - #9464K16 McMaster-Carr

o SPECS
+ AS568A Dash Number: 011
+ Typ:e O-Ring
+ System of Measurement: Inch
+ Width: 1/16" (1.5875mm)
+ Inside Diameter: 5/16" (7.938mm)
+ Outside Diameter: 7/16" (11.113mm)
+ Material: Viton
+ Durometer: Hard
+ Durometer Shore: Shore A: 75
+ Temperature Range: -15° to +400°F
+ Color: Black
https://www.theoringstore.com/store/index.php?main_page=product_info&products_id=38145

NAPA cross reference on this o-ring is:
Part Number: BK 7272011
Product Line: Balkamp
Dimensions : 5/16" I.D. x 7/16" O.D. x 1/16" W ( 7.938mm I.D. x 11.113mm O.D. x 1.5875mm W )
Material Type : Buna-N-Nitrile
SAE or Metric : SAE

QUESTION: are the upper and lower O-rings different (I'm assuming so because Triumph gave them different part numbers). - they are different thicknesses.

The upper o-ring is approximately 15mm outer diameter with a 3.5mm cross-section, while the lower o-ring is about 15mm outer diameter with a 2mm cross-section

2mm wide lower: https://www.amazon.ca/gp/product/B07GJK53QJ/
3.5mm wide upper: https://www.amazon.ca/gp/product/B07JWCD86K/
I'll give these a go and see how they do.

https://www.ebay.ca/itm/156327987779 - that's high-larious! Forty bucks for an (as in ONE!) 20 year old O-ring! It ain't just the stealerships who cane you for these parts (when they deign to sell them).

https://theinjectorshop.com/en-ca/products/fuel-injectors-rebuild-repair-o-ring-kit-for-triumph-sprint-st-tiger-1050-2007-2009?_pos=1&_sid=00ce905cd&_ss=r

Hmm, do 1050 tigers use the same O-rings/injectors?

2007 Tiger 1050 parts:
O Ring, Injector, Upper T1245016 (same as 955i part)
O Ring, Injector, Lower T1245006 not - damn it!

Hey, Tim. Try using AI to solve this problem! Here's Perplexity.ai (on 'pro' mode!)



Adamantly and repeatedly incorrect. So much for HAL 9000 fixing the Tiger. I'll give those Amazon parts a try and let you know the results.

NAPA details: https://www.napacanada.com/en/p/PSH71169 Part #: PSH 71169
.301 ID X .070 W (7.645mm ID X 1.778mm) why only show the inside diameter?

Deja vu: https://tkmotorcyclediaries.blogspot.com/2023/10/finding-your-way-around-oems-giving-up.html

Based on that the 15mm outside diameter 3.5 and 2mm thickness is a pretty close guess.
Why doesn't NAPA provide dimensions: https://www.napacanada.com/en/p/ELR429060. I'm going to run over to our local with the two O-rings and see if they'll help me match them up, but the site could be more helpful.

Going for (yet another) fueling fix on the 955i Triumph Tiger

 It's a tricky thing finding the parts you need on a bike no longer supported by its manufacturer, but I keep getting lucky with quality aftermarket providers, in this case Quantum Fuel Systems out of California.

Ordering was easy, transport was astonishingly quick and transparent and I had the kit on hand less than 48 hours after I ordered it. I haven't had many better shipping experiences.

I went with Quantum because they had a full kit including hardware and a fuel filter (because none of that is available through the dealer). No instructions came with the kit but the pump, filter and strainer (all included in the kit) are an easy fit, especially when you've got the original sitting in front of you to work from. The whole thing took about half and hour from removing the plate it's attached to on the tank through to having it back together again.

This is where the fuel pump plate bolts to the tank.

The original pump (mounted in front), fuel filter (behind) and strainer off to the right.

Disassembly was straightforward. One of the nice things about an immersed system like this is that rust can't get at it.

The new bits installed, very straightforward.

You can see the difference in colour with the strainer. The old one was stiff as well as discoloured. With all new parts I'm hoping this magically restores the Tiger to regular fueling duties. I've seen some other comments suggesting that this is the silver bullet when it comes to old Triumph 955i fueling headaches.

It's all back in the tank again now. I'll get the bike back together and if the snow holds off take it for a spin, hopefully with a sense of resolution.

Update

Got it back together again and the new fueling bits have solved the starting problems (it fires on the button again) and it idles steadily again - a bit high even (but I'd been messing with the fuel maps to try and bump up idle speeds). I've since reinstalled the stock map and it starts and idles well.. But as with everything fueling related on this thing, one solution has caused another problem.

Previously the throttle worked fine but it wouldn't start or idle. Now it starts and idles but if you touch the throttle is stalls. My first thought is that this might be because the new throttle cable wasn't adjusted right, so I loosened it off and gave it the required slack the manual suggests. It still stalls when you touch the throttle.

The next thought was perhaps the new fuel pump and filters have messed with the throttle body synchronization (this bike is notoriously finicky about this). So, I took the fuel tank off (again - can't count how many times now) and rebalanced everything yesterday. We've got our first snows of the year now so I can't take it for a spin, but I'm hoping to have it all back together (again) this week and see if I've got a working Tiger.

If you want a sense of how perilous fueling is on 955i Triumphs, Classic Bike Magazine (my go to for genuinely helpful advice on keeping old bikes running since Practical Sportsbikes closed down and got folded into CB who now support a much wider range of machines) had a piece on the 955i Speed Triple (one of my all time favourite bikes). Page two had the enlightening piece to the right.

Fueling on these old Triumphs is a known headache. I've sold on bikes I've become frustrated with before and the problem hangs in my mind. Rather perversely, I need to figure out what's wrong with the Tiger before I sell it rather than just selling it on in this state. Not knowing what the problem is will drive me nuts. On the upside, if I become one of the 'very few people with experience of the Segem fuel injection', I'd be able to pick up a 955i Speed Triple that isn't working for a song.

Doing this after the Tiger, now *that* would be perverse!