Sprint Stumble Around 3500 Rpm

Mechanic is probably right, bike is perfect for riding. It's probably the EU emissions compliance tuning that is causing the issue.

 

If you fuel map is similar to my 2010 Speed Triple then there is a do in the map at 3500 rpm at 10% throttle or there abouts
I had a remap done on an earlier bike that eliminated this and she ran beautifully,
As said it is a lean spot in the map for the bike to meet environmental regulations, the whole map needs smoothing out

 

Triumph Fan.
Forget the Triumph map. They are restricted as to what to offer. Get your bike Dyno'd or get one of the race boys to map it for you.
Ride Safe.
Joe.

 

After fixing some issues with mine such as perished/leaking vacuum fittings, IAC valve broken, barometric pressure hose perished/leaking, throttle bodies out of balance and ditching the Pipercross air filter and carrying out a comprehensive service I was left with my bike having what was sounding a little like a misfire or a 'fluffy' throttle. It was easily demonstrated if you held the throttle at 2.5k or rode in first at the same rpm.

What I'm currently in the process of, after a suggestion from a work colleague, is running injector/fuel system cleaner through it, I'm 60 miles into the process now. I discovered that the ingredient that does the work is PEA (Polyetheramine). Many fuel system cleaners don't have this which is probably why I've never felt that these did anything worthwhile.

I'm using BG44K (tried to get hold of Chevron Techron Concentrate but DHL fouled up the Ebay delivery) and I am without doubt noticing smoother fuelling and the 'feature' I had at 2.5k rpm is fast disappearing, if not gone. My bike is a 2001 with only 11,000 odd miles on it which isn't what you'd call a healthy mileage for it's year so it's obviously got/had fouled injectors.

This works best with a series of short journeys, my commute is 17 miles each way for example. This generates heat cycles, the injectors are operated at varying levels and the cleaning agent is allowed to sit in the injectors and fuel system doing it's work at dissolving the deposits before the next cycle. A single 200 mile trip won't be as effective.

I'm hoping for a lasting improvement, there's enough left for two more tanks which I'll run through back to back. I was ready to pull the injectors and get them cleaned but thought why not try this first.

 

The flip side of the coin is that an 18yr old bike averaging less than a thousand miles a year has had plenty of opportunity to dry out and gum up its fuel system. The more volatile elements in the fuel that keep things clean evaporate fastest......
I can well believe it needs a clean out!

 

I'm no expert by any means but through my recent and extensive reading I was left thinking that there are only a few products that are capable of cleaning properly; those with PEA. Redex may be good for maintenance once you have the fuel system in a good place but, based on what I've read, it may not clean up heavily deposited injectors. I've no evidence for that of course.

I'm fairly certain mines getting better, only 80 miles in so far, so we'll see.

 

I get 48mpg based on what goes in when I fill up. What are you getting?

 

I had an 08 Sprint with a TOR exhaust and map. It still had the hole at 3500 to 4k. I looked at the map and the dip in the fueling is quite obvious so I just lifted the numbers to give smooth progressive lines on the graphs and it was fine after that. Obviously a spell on a dyno would be better but it was good enough.