A tale of two cans

On Friday 9 August I managed to lose the can off the back of my Sprint GT and needed to replace it.
I had had several issues with the can (including poor fitting) which I had communicated to Trident (Wolf Racing) so was rather disappointed when they offered to replace the can at the full RSP even though it was less than 2 months old.

A Google search threw up a new name that I had not encountered on my previous search for aftermarket exhausts for this bike only two months earlier. The product and price looked good and their reviews (from riders of different bikes) all seemed positive. I'm guessing they are newish or not very big as a lot of the reviews on bike forums started with Has anyone heard of SP Engineering ... or has anyone tried ...

Price, ordering and delivery

  • SP Engineering was £60 cheaper. Fair enough, Trident is a pretty big name in the Triumph world.
  • Both delivered within two days of placing the order.
  • I ordered on-line from SP and chose to phone Trident because their website wasn't great, again fair enough - they are exhaust manufacturers not software designers or engineers

Fitting

  • The SP can arrived with printed fitting instructions, the Trident didn't. Arguably if you need instructions to swap this you shouldn't be let loose with a spanner.
  • Both were easy to fit.

After initial fitting I had my first correspondence with Trident about the can: It appears that you have sent the incorrect hangar, designed for a much larger exhaust. Please could you send me the correct one.
The response:
The hanger is as it should be - it's designed to take the weight at the bottom but not grip it so it doesn't rub the carbon - having said that most people simply don't use it at all as the cans are light enough to self support
I elected to go with most people. Foolish me.

Appearance and design

  • Both products looked stunning when I unpacked them from the box
  • The Trident uses alloy billets where the SP uses stainless steel, I felt that this looked cleaner
  • The SP's carbon sleeve is attached to the billets using traditional rivets while the Trident's is neatly fitted over - again giving a cleaner appearance
  • The removable baffle / DB killer on the Trident lives in the link pipe end of the can. The SP one is a traditional slide into the back affair that is held in place by a screw. Once again a cleaner appearance but at the expense of ease, you have to detach the can from the link pipe if you want to change the sound
  • The absence of a hanger looks neater.
  • The trident was supplied with a discreet stick on gel label which I chose not to attach. The SP had no label or makers plate but does have SP Engineering etched into the rear rivet band.
  • The Trident has no markings on it to certify fitness for road use, but more importantly none declaring it unfit. The SP is BSAU marked

On this basis it has to be said that the Trident can is better looking. But I never felt that it quite suited the bike. I had several people comment on this. In fairness I chose it knowing what it looked like. I did want a stubby can, but stubby does not mean skinny. So for me the SP can looks better on the bike - but that is of course personal opinion.
However, the aesthetics of the Trident can do come at a cost ...

Build quality / engineering

  • The hanger on the SP fitted and has been installed
  • The pipe on the end of the Trident canister was very slightly out of round. This meant that no amount of torque on the clamp could create a perfect seal and I had to resort to a bead of silicone to cure the leak.
  • The sleeve rotated freely on the Trident, this cause another leak. I queried this and received the following response:
    You will often find small leaks between the end billet and the stainless stub coming out from it - alloy expands much faster than stainless so we have to leave a very small gap to allow for this and usually when the ken (sic) gets hot it seals up and only leaks slightly as it contracts again when cooling - it really won't cause any issues but if it bothers you just run a bead of clear silicone around the join between the end plate and the inlet stub
    I used the silicone because it leaked profusely when hot.
  • Both products used clamps to secure the can to the link pipe. Just my opinion but I think springs are much easier and more secure - I have certainly never lost one off the back!
  • I complained that the Trident seemed to yellow very quickly. Response was that if I had polished it the polish had yellowed and I should use T-cut. A light polish with T-cut did remove most of the yellowing. Its too early to comment on the SP and as I had polished the Trident the diagnosis may have been correct

So there you have the costs of the cooler aesthetics - at least that's my experience. It may just have been a Friday exhaust - but I wasn't taking the chance when I replaced it.

The sound

Please note that I only ever rode with the Trident can with the DB Killer in. So far I have only used the SP with it out.
I previously described the Trident as producing a lovely growly sound. I would describe the SP in exactly the same way, but the sound is completely different. Where the Trident is a snarling angry teenager the SP is altogether more grown-up with a much softer sound. This makes it sound quieter although a decibel test may well prove me wrong. I do enjoy the sound of both. I did not dare remove the baffle from the Trident because based on the sound with it in I felt this would attract unwanted attention from members of our law enforcement agencies. No such qualms about the SP. I suspect that the SP (even without the baffle) would draw slightly less attention going through a housing estate late at night. The one area where I definitely prefer the SP's sound is when it comes to popping on the overrun. This sounds very harsh and aggressive from the Trident. The softer sound from the SP makes it sound more like a burble and fairly pleasant. By the same token I prefer the Trident when using my right hand to shout at drivers who do particularly stupid things. Oh and I have managed one full blooded backfire on the SP - not deliberately induced I might add. At low revs in traffic I can hear the gearbox whining with the SP. This is not somethingI ever noticed with the Trident on.

I suspect the main source of the difference is that the SP has a bigger bore and presumably more padding in the larger diameter sleeve.

I did briefly pop the baffle in to the SP and ran it for about 30 seconds on the centre stand. Obviously not enough time for a proper assessment but it sounded higher pitched and much more aggressive and sporty - and not actually quieter. Not dissimilar to a 1980's Kwacker with a Kerker 4 into 1

Performance and fuelling

Remember: Trident with baffle, SP without. This is purely subjective and may not be confirmed by scientific testing.
Both websites claim that their products will work with standard mapping. And of course they do. However both would benefit from a custom map. My bike is going in for a dyno run tomorrow so no further comparisons will be possible. I have only used the SP for 70 miles of commuting, half of which was in the rain.

  • Both have a slightly snatchy throttle at low revs
  • Both seem to cause a slight loss in power at low revs
  • Both pop excessively on the overrun. This is of course a feature that Triumph's are renowned for. The standard can seems to do the same, you just have to remove the earplugs and listen harder to notice it.
  • Warm starting requires a few swings of the motor rather than an instant start with both.

Trident claims that their system was developed specifically for the bike. Even to the point of warning me to stay clear of general purpose cans with a custom link pipe. I was told that, based on their experience, the smaller bore works better with the triple - especially at low and mid range. That may be the case but I always felt that the bike felt restricted with the Trident across the rev range. This was possibly confirmed by the massive increase in acceleration when the can did pop off at full throttle. I don't intend to repeat that particular test as its an expensive one. My impression is that the bike is far more responsive with the SP at low and mid range and revs far more freely and willingly. I haven't tried enthusiastic acceleration but hopefully the reduction in back pressure will reduce the risk of losing another can.

I will be going ahead with the dyno session tomorrow. This was originally booked with the Trident exhaust in mind and I felt that it was definitely needed. I don't feel that it is quite as necessary with the SP (possibly even less so with the baffle in) but I am expecting a noticeable improvement.

Conclusion

I was naturally devastated the day I had to turn around and retrieve my exhaust from the tarmac. Yes it had its fair share of problems but I believed I has worked through them and was not planning to replace it. it would be grossly unfair to say that it was a fortunate incident. But I have ended up with something that I much prefer to what I had before. It's just a shame I had to buy twice to reach here. And I'm sure there will be times when I miss the angry teenager.

Baffle update

After a few days I have put the baffle in to assess the difference. My initial 30 seconds in the garage late at night obviously wasn't enough. It does have a higher pitch and is significantly quieter. But not more aggressive or sporty and nothing like an 80s kwacker. I can't really tell the difference in performance until I get over 6k and WOT. Might be my imagination of course. I believe the expected power gain at top end from removing the baffle is about 2%. Not sure I'm qualified to detect a 2% gain.