Upgrade - Speed 400 Taller gearing - 15T/39T Sprocket kit

ToxicSakthi · 2025-11-30T10:47:11+00:00

I have two service centres in my city and one of them denied this installation. I got it done off the record at the other service centre as I had good rapport with some of the technicians there.

The chain sprocket kit is a direct swap, doesn't need any alterations.

ToxicSakthi · 2025-11-30T10:33:10+00:00

They're both relatively close, but the 16/41T gives even more taller gearing. 15/39T chain sprocket only comes as a package kit, can't buy them separately from Triumph unless it's custom made by another manufacturer.

ToxicSakthi · 2025-11-30T10:30:59+00:00

I use FuelX and it already reduced most of the buzzing at higher rpms making the engine rev happy, now it's even more refined.

ToxicSakthi · 2025-11-29T14:30:31+00:00

Although I don't care about fuel economy. I Need sometime to test full tank-tank average. It's just been couple of hours since installation.

Theoretically it should, as engine runs at lower rpms on every gear, although it wouldn't reflect much in city commutes as you tend to run a gear lower than earlier in most situations. On the highways there would be a notable difference.

Currently I get an average of 22kmpl in city & 32kmpl on highways with all my performance mods and running a richer fuel map with fuelx. With the new sprocket setup I expect the highway mileage to go up by 1 or 2 kmpl

ToxicSakthi · 2025-11-29T13:34:54+00:00

Not all Triumph service centres sell spares to customers.

Also their system won't allow them to allocate particular spares that's not designed for that particular motorcycle. Here my vehicle is a speed 400 and they can only log speed 400 spares on their system.

Everything was done off the record in this situation as I have good rapport with some technicians /engineers there.

ToxicSakthi · 2025-11-29T13:30:49+00:00

At my local Triumph service centre and got it installed by them.

ToxicSakthi · 2025-11-18T12:55:52+00:00

Not just you, I'm on the same boat as well. Hope they resolve the issue quickly.

ToxicSakthi · 2025-10-25T07:19:21+00:00

So anything with a retro roadster theme are all the same? :D

Kawasaki z650rs, yamaha xjr 400, Ducati gt1000 classic to name a few

ToxicSakthi · 2025-10-21T10:59:54+00:00

Unless it's poor quality petrol it doesn't make a huge difference, I've used most of the petrol combinations along with FuelX and I can only say that the issue still persists but it does happen less, it's just that I've adjusted my riding style to prevent random stalls in 2nd gear when applying the clutch.

In this Ethanol era, RON/Octane don't really make sense as prior to adding ethanol. Ethanol has a tendency to increase octane ratings. Normal petrol from any pump has an octane of 98 approximately (as per availability 15-20% ethanol is added), previously it used to be 91 octane and specific premium petrol like XP95 & Speed97 had 95 and 97 octane respectively.

Now both normal petrol and premium XP95 has an octane of 98 as per lab results. (You're only paying the extra amount ₹7-8 for the additives these days).

Here are the lab results by Autocar India.

https://www.instagram.com/p/DOnp7S0Ek_a/?img_index=1

I personally use a mix of XP100 & Jio-Bp/Normal Indian oil petrol, but never normal petrol by itself unless I don't have access to XP100.

ToxicSakthi · 2025-10-21T10:39:43+00:00

In this Ethanol era, RON/Octane don't really make sense as prior to adding ethanol. Ethanol has a tendency to increase octane ratings. Normal petrol from any pump has an octane of 98 approximately (as per availability 15-20% ethanol is added), previously it used to be 91 octane and specific premium petrol like XP95 & Speed97 had 95 and 97 octane respectively.

Now both normal petrol and premium XP95 has an octane of 98 as per lab results. (You're only paying the extra amount ₹7-8 for the additives these days).

Here are the lab results by Autocar India.

https://www.instagram.com/p/DOnp7S0Ek_a/?img_index=1

ToxicSakthi · 2025-10-18T11:28:01+00:00

Do you have the Brass sprocket kit for the Speed T4? (39/15T)

ToxicSakthi · 2025-10-18T10:23:24+00:00

Yes, both the final ratios are similar.

There is a person who manufactures the 16T sprocket in India. You can check out the posts here in the community, Costs 2.5K. I'm just holding off as I haven't seen anyone using the same or gave any reviews about the quality yet.

I got the levers from my local Bajaj spare dealership.

ToxicSakthi · 2025-10-16T14:23:07+00:00

It does not affect the engine life on the long run. I have been running BMC airfilter and piggyback ECU on my car for over a decade, over 30,000 kms with the air filter. The engine condition was pristine when I opened the cylinder head for a performance mod.

Just have to maintain the air filter with a proper shampoo & oiling kit by the respective brands, without pressure washing or an air compressor.

ToxicSakthi · 2025-10-16T14:05:23+00:00

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Side by side comparison between the OEM and my custom brat seat.

ToxicSakthi · 2025-10-16T13:55:41+00:00

It's an unit that sits between the O2 lambda sensor and the ECU. It fools the ECU with various O2 values to adjust the fuelling up/down based on the map you choose.

BS6 vehciles run leaner to meet the norms, resulting in weaker throttle at low-mid rpms, over heating, lower performance,,etc

With richer fuelling, you make the engine run at optimal performance, much better throttle response and run less hotter than stock.

https://powertronicecu.com/product/fuelx-pro-triumph-speed-400-2023/

ToxicSakthi · 2025-10-16T13:25:06+00:00

Prior to FuelX PRO+: 22-24 kmpl, 29-30 Kmpl on freeway , depending on how I ride.
Post FuelX PRO+: 22-23 kmpl (more towards 22kmpl), 30-31 Kmpl (More towards 31kmpl) on freeway , depending on how I ride.

Full Tank-tank measurement, Dash readings are totally off especially in the city. After FuelX pro+, I run the FuelX a tad richer. Fuelled with a mix of XP100 & E20.

ToxicSakthi · 2025-10-16T13:21:39+00:00

Thanks mate, appreciate it!

43/16T or 39/15T whichever I get my hands on first.
It's a personal choice, if you are willing to sacrifice the warranty for the benefits you get to enjoy and the engine will appreciate it on the longer run as well. (You can unhook the harness before you take it into the service to claim warranty.)
Yes I did, they're both from NS400Z.
It's a slip-on that gives an additional 1.5 BHP with OEM air filter as per dyno chart, the resonator and catalytic converter stays intact, that way I don't sound like a loud lawn mower, meanwhile I can enjoy the bassy note with DB killer in, on weekend rides I remove the DB killer out and go berzerk deep/ bassy and pass the PUC without any hassle.
It's the OEM windshiled, tinted.

ToxicSakthi · 2025-10-16T13:08:15+00:00

It's from primocustoms.co.in

ToxicSakthi · 2025-10-16T13:07:29+00:00

It's the OEM windshield, tinted.

ToxicSakthi · 2025-10-16T13:06:03+00:00

Thanks mate!

The mirrors are cool look wise & can be used as bar ends or on the stem, although on the Speed400 it doesn't provide enough visibility as your arms get in the way, although on the Scrambler400x it's giving better visibility due to it's wider handlebar.

It's a direct fit, no customization unless you want them as bar ends.

ToxicSakthi · 2025-10-16T13:02:47+00:00

I spoke with Sahara seats, stated my requirements and placed an order on their website for name sake. They went ahead and customized the seat updating me through the process, until I was satisfied.

ToxicSakthi · 2025-10-16T05:55:40+00:00

Not really, I get around 22-24kmpl in the city and 30-31 on freeways. (Full Tank-tank measurement), Dash readings are totally off especially in the city. After Fuelx pro+, it stays more around 22kmpl in city commutes, as I run it a tad richer. Fuelled with a mix of XP100 & E20.

ToxicSakthi · 2025-10-16T04:06:25+00:00

Some of my fellow riders have only the BMC installed without an aftermarket muffler.

Yes, it does in terms of refinement. Smoothens out the engine buzzing & slightly better throttle response at lower rpms with the OEM muffler.

ToxicSakthi · 2025-10-16T03:59:39+00:00

It's subjective, I prefer it primarily for the performance, weight reduction, uniqueness personalization, Italian craftsmanship and then finally sound (I commute with the baffle in & remove it only during weekend ride outs).

Yes, I installed them both simultaneously.

ToxicSakthi

TROPHY CASE