De-cat X Pipe on New Bonnie?


Looking for some voices of experience and wisdom here, failing that I’ll take whatever you throw.

I am taking my Bonneville T100 in for its first 500 mile service tomorrow morning. When I called and booked it in I asked whether it was worth upgrading the exhaust to the Vance & Hines slip ons. The guy in the servicing team told me they make a bit of a difference but not a massive difference. He suggested a better (and cheaper) alternative would be to switch out the catalytic converter and replace it with a TEC x pipe. This would give me a nice bit more volume and sound and would add a touch more power.

I have done plenty of googling and forum reading about this and I’m still on the fence, so I’m interested in the worldly wisdom of this forum.

My concern is whether it might negatively impact anything (warranty, stability, legality, performance, whatever). Also, wondering if anyone else has done the same with a new triumph water cooled v twin 900 and what their experiences and opinions are.

Also, I was asked if I want to borrow a loaner while they service my bike. I said yes, and now I’m wondering what they’ll give me and if that will result in me deciding to take a hit and trade up for a new bike (ahem, @learningtofly)

Thanks in advance for any input/abuse.


Ah yes, the old “Do you want a loaner” trick :joy:

I’ve heard good things about the x-pipe, and that’s probably the route I’d go. I’m not aware of any downsides.


i decatted my 2010 tiger 1050
i didnt buy a decat pipe i just removed the cat from the exhaust headers
it makes a massive difference but you will need a remap


As above it’ll need a remap. On the earlier 2010 to 2015 EFI Triumphs you could buy the link cable hook the ECU up to a laptop and remap via TuneECU ( assuming that you knew what was what, its not a toy but a professional piece of kit which can equally enhance performance or destroy engines.

The bottom line is if it doesn’t say Triumph on the box the warranty will be invalidated. It’ll make more noise which makes it feel more powerful, the reality being the extra power will not be measurable and will most probably be lost in a snatchy engine performance.

If you wanted more power maybe a T100 was not a good starting point.

May be better to ask the question elsewhere too (

If the loaner is a Street Triple 9or any other triple) you’ll be having second thoughts on the T100


The loaner was a street scrambler. Nice enough but prefer my T100 so no danger of a trade in.

In the end I bit the bullet and went for the decat. They fitted the TEC x pipe and I also switched the tank badges for the bar-style ones and switched the mirrors to bar ends.

Looks wise I’m pleased with the tweaks. Disappointed they didn’t wash the bike for me (it could do with one after this weeks weather) but maybe that was expecting too much!

Based on the 30 minute ride home this evening, the decat makes a worthwhile improvement to the sound of the bike. It has a louder, deeper rumble now which is what I was after. As National Treasure said, if I wanted power I wouldn’t have gone for the T100. My plan B (Monster 825) was the power option but my heart went with classic looks. I’m now wondering at what point I mention to the missus that I need a monster to cover all bases…

Anyway, back on topic. The mechanics at Triumph told me there is no need for a remap on my bike (2018 T100) as the bike computer is able to analyse the oxygen and adjust fuelling as needed anyway. Might be nonesense, I don’t know enough about it, but triumph mechanic in a dealership vs “I read some post on the internet” led me to go with the Triumph dude for now. Still might add the V&H pipes in summer which (according to “people on the internet”) would come with a remap. Whatever.

Finally warranty. I asked if the decat would invalidate it. The dealership told me “don’t worry about it - we will honour your warranty, it’s fine”. Obviously not in writing but again, whatever.

Verdict: based on a 30 minute ride home, I’m pleased with the noise upgrade. Let’s see how it goes over time.


That’s interesting - I was told something similar (in respect of an ECU that “learns”) when I asked about putting a Yoshi on my Street Triple. Anyway, it all sounds good.

Incidentally, I take my Triple in for its 500 mile spa next week. I’m thinking of taking another loaner out for a couple of hours… :man_facepalming:


I like that " I read some post on the internet" how true and how much nonsense is spoken out there.

To be honest the T100 will have more than enough stock power to keep pace with anything on public roads, just ride it in the upper quarter of the rev band and take it anywhere.

Here’s one I took somewhere earlier



Ecu s can cope with little changes
But they can’t cope with big changes
I would recommend you ask someone that remaps bikes
Try HM in Kent
They do all my tuning for me


Just to put those little changes the ECU can cope with into perspective. The ECU is designed to and can cope with fuelling fluctuations such as the difference between an engine starting from cold in mid winter and a fully warmed up engine sitting in city traffic mid summer. If you make changes to the fuelling or exhaust systems the ECU will not be able to cope with the fuelling requirements at the extreme ends of that range. The all too familiar symptoms can include flooding and difficulty in starting from cold and miss firing or cutting out at low revs when hot.

The irony here is that so many of these performance modifications actually result in a loss in performance because the limitations of the ECU are not taken into account.


I just wanted it to sound a bit more exciting :confused:

I suppose if I start noticing problems I’ll look into a remap.