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TTP 904s Sports Big Bore Kit Reviews for the product - TTP 904s Sports Big Bore Kit (Back to product)
7 Product Reviews - Average rating 5 / 5 (Best Rated | Worst Rated | Most Recent | Oldest)

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904S Kit

- 10th May 2021

I now have all the power I need. The bike is so different now. Raised gearing and greater millage, engine is more reactive now, and the feel is right.

Triumph Tracker.

- 24th September 2020

I have fitted the 904s kit with smooth bore carbs, performance ignition, gas flowed head, 2 into 1 pipe & lightened crank rotor. It makes a big difference!

The 904 kit is the core of the performance gain.

Transformation !

- 19th August 2019

After deliberating for some time I had the 904 kit installed on my 06 Scrambler and haven't stopped smiling since, the bike is transformed at all levels. I had TTP do the installation and highly recommend their services.

Between this and a new bike..

- 19th August 2019

Awesome upgrade.

I did the installation myself last winter/early spring with a Haynes manual and some help from YouTube/rat forum. Wouldn't call it easy, but it can be done. Take your time, adhere to torque specs, stay organized, etc.

I also have performance cams, and the bored n flowed throttle bodies. All said and done, my dyno reading was 80hp at the wheel and 60 torque. The guys at the shop also mentioned their dyno machine is pretty conservative compared to others, and it might have read closer to 85/90HP somewhere else.

It's close enough to the new Thruxton for me, while maintaining air cooled simplicity and keeping me outta monthly payments.

Much more fun to ride now!

904 big bore kit w/ performance cams

- 09th July 2019

I'm about 500 miles...or 800km for those using that other system...into TTPs 904 BB kit & their performance cams, fitted with D&D full exhaust and stage 2 mods rocking K&N intake pod filters, installed on a 2010 thruxton 900...the hype is real folks, the power gains are no joke!!

I have yet to really push it, but oh, my the top end is SO money. Low end on Thruxton's already rocked(s), so add additional 30-35% more power and add that up.

As far as the install...I did it myself, with only oil changes and brake pad replacement experience prior. The learning curve was steep, bloody vertical at times, but with triumphs maintenance manual, various triumph.rat post reads, a few YouTube videos and an extra clutch lifter plate later, TTPs 904 BB kit was successfully installed. Was never overwhelmed during but took 2-3x as long as expected.


TTP were there from start to finish. Quick and thorough email replies, addressing any question. Oh ya, even their packaging rocks!!

Is that enough to convince you to buy TTPs 904 BB kit? GET SOME!!

Scrambler TTP 904s Big Bore ? Excellent!

- 22nd January 2019

For anyone that is thinking of laying out your hard earn't cash and buying this big bore kit from Triumph Twin Power, I would say go for it!

What a difference it has made to my 2016 Scrambler. From stock it was always a bit of a struggle when overtaking on the hills where the bike would run out of puff. Not now with the big bore kit and TTP tune installed. I just select fourth gear roll on the throttle and the bike eagerly launches forward and overtakes with ease. Snick it back into top gear and try and wipe the smile form your face! The mid-range punch this engine has now is really something all Triumph Twin owners would be impressed with.The engine is so responsive now and the bike really gets up and accelerates hard and fast right through the rev range. The difference really is night and day with this top quality modification, you will not be disappointed.

Hat's off to Mike at TTP for his extra work in getting the right tune sorted for me here in NZ, also to Mike at TT3 in Canterbury south island for his support and service in supplying me the parts via TTP in the UK. Service really is second to none when dealing with these guys.

Great so far!

- 28th September 2018

Due to a piston seizure on my 2014 Speedmaster (don't ask), I needed to have the engine repaired in an economical way. The new 904s Sports Big Bore Kit seemed to be the best way available to get my bike back on the road and I was more than pleased to take one of the first kits to be delivered.

With 600kms of gentle riding to run the bike in completed, the engine is smooth, more economical and has more mid-range punch than it did before. Given the CC boost is only from 865 to 904 I wasn't expecting a step-change in performance but the bike does feel stronger overall and the economy boost is around an extra 30kms per tank so no complaints at all on that front!

Fitting was challenging in a few places but the gasket kits, clutch springs and start safe additions were all very well thought-through according to the mechanic who completed the work for me.

The exchanged cylinder barrels are matt black rather than having the original metal fins, but this does not detract from the look of the bike in my opinion and I believe the metal-finished versions are available now.

Overall I'm very pleased to have a working Speedmaster back to either enjoy or sell-on and the team at TTP were helpful throughout, offering advice and tips whenever we needed them.

The only downside for a non-engineer, layperson like me is the cost of the kit... I have no baseline of course but over £1200 is a lot of money for us and as a result, this will be our first and last Triumph. But without TTP's kit it would have been more than £2500 for a new engine!

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