Running Lean

In practice, I think the only thing you'll achieve from fitting a K&N is a slightly lower cost for air filters through time, possibly a more throaty induction roar and poorer filtration of particles in the inlet.....:nenau

Thanks Schtum ( & Fanum ) - the point I was trying to (gently) make to the OP. The OE filter passes more than enough air, & filters well, so I genuinely am nonplussed as to why anyone would use it on a road bike.
I have got to know Geoff at Hilltop quite well, & I know he shares this view. The last time I was there he had a customer there who had a K & N, a very dry K & N at that, fitted, & Geoff pointed this out, saying in effect "Don't be daft; put an OE filter back in".
 
In practice, I think the only thing you'll achieve from fitting a K&N is a slightly lower cost for air filters through time,

I doubt there is a saving once you've bought the K&N filter cleaning fluid and filter oil and factored in the time wasted in cleaning, drying and re-oiling the filter, and clearing up the mess that's left .:D
 
A nice exhaust system with remap will be better than the standard system with remap and they look good. :)

K&N air filter is pure snake oil.
 
A nice exhaust system with remap will be better than the standard system with remap and they look good. :)

K&N air filter is pure snake oil.

Agreed although without doing a full set of tests difficult to really know what difference each one makes. My 08 Hexhead has remus headers and Akrapovic end can - after the Hilltop experience (I replaced the K&N with OEM filter) its putting out 107bhp at the back wheel (from 87 bhp) but more importantly, torque went up over 30% and is at 5.5K revs instead of 7.5K revs. That makes a huge difference to both the fun and ridability of the bike. On par with a basic WC motor I would guess.

Anyone want to buy a K&N, Accelerator Module or Wunderlich Fuel Controller?
 
Agreed although without doing a full set of tests difficult to really know what difference each one makes. My 08 Hexhead has remus headers and Akrapovic end can - after the Hilltop experience (I replaced the K&N with OEM filter) its putting out 107bhp at the back wheel (from 87 bhp) but more importantly, torque went up over 30% and is at 5.5K revs instead of 7.5K revs. That makes a huge difference to both the fun and ridability of the bike. On par with a basic WC motor I would guess.

Anyone want to buy a K&N, Accelerator Module or Wunderlich Fuel Controller?

I'd suggest riding the WC and the upgraded 08 bike back to back - the WC is a lot quicker and and feels like it has a lot more torque. There is a lot more than in it than the above figures would suggest.
 
I'd suggest riding the WC and the upgraded 08 bike back to back - the WC is a lot quicker and and feels like it has a lot more torque. There is a lot more than in it than the above figures would suggest.

You haven't ridden my bike have you so how can you say that? The figures speak for themselves which unless everyone rode my bike is all you can go on. Nobody has put their WC on a dyno yet...or have they?

Forgetting about the tongue that is very much in my cheek when touting bhp figures in comparison to a WC, the OP is about the lean running issue on a Hexhead. I rode my bike to Hilltop with Remus headers/Akro end can and an accelerator module to be on the safe side. I had already replaced the K&N with a paper OEM filter before the trip. My guess, which is all it is, is that you'd be OK if you replace the K&N with a paper filter even without anything else to richen the mixture - just don't pin it on the throttle all the time. By all means put the K&N back in at Hilltop should you wish but I doubt there's any performance gains worth noting.
 
I was offered one of these which looks great on the bike.

http://www.akrapovic.com/en/Motorcy...+Racing+Line+(Titanium)+R+1200+GS+/+ADVENTURE

Hilltop told me that any aftermarket decat system without baffles and plain 95RON fuel it will be borderline especially on motorway. Mine especially so. A free flow air filter would absolutely not be a good idea with any free flowing exhaust system. It will run too weak and the valves could easily get damaged.

Fitting baffles (which my Ti seriously needed) and using posh petrol keeps my bike the right side of OK until I can get it remapped.

Higher octane advances the spark timing so more energy goes into the pistons and less gets thrown down the exhaust pipes so the exhaust runs cooler.
 
i ran/thrashed my 08 gsa with decat headers k&n open remus all through france, spain, portugal, no problems and no performance gains, it did run better when i put the power commander on tho:blast
 
The bikes run lean up to 4500rpm, then come into line as the fuelling changes from closed to open loop. Mine was at 17.5:1 below and 13.5:1 above the 4500rpm point.

A motorway slog to Earl Shilton at 3000-4000 rpm is still within the lean zone.

As for the K&N debate, its just an air filter designed to be re-cleanable in harsh environments like the Baja 1000 race and a tiny performance gain for a considerable outlay plus a faff to clean and re-oil.
 
Accelerator module

Thanks for all the feedback........ even for those people slating my use of a K&N. I've always used them with no problems, however it seems a bad choice on this occasion. I will revert back to the standard filter for the journey down to Hilltop though I will put it back in after.
Johnny Boxer.......... if I need a bike that accelerates faster I'll use my GSXR1000.........which also has a K&N, thanks for your valuable input.
I have no experience with the accelerator module, is it worth just putting one on for the journey down? Do they richen the mixture or something, I've no idea.
 
Thanks for all the feedback........ even for those people slating my use of a K&N. I've always used them with no problems, however it seems a bad choice on this occasion. I will revert back to the standard filter for the journey down to Hilltop though I will put it back in after.
Johnny Boxer.......... if I need a bike that accelerates faster I'll use my GSXR1000.........which also has a K&N, thanks for your valuable input.
I have no experience with the accelerator module, is it worth just putting one on for the journey down? Do they richen the mixture or something, I've no idea.

The Accelerator module plugs into the airbox connections and basically fools the ECU into thinking the ambient temperature is less than it actually is. I checked mine on a GS911 and it drops the temperature down by 20 degrees centigrade. That forces the ECU to richen the mixture up which it would do naturally if it really was colder. Its a bit belt and braces but as a compromise it does seem to work OK and is only 5 minutes effort to connect into the loom. Its one of those things really, until you put your own bike on the dyno you don't know how lean its actually running and therefore how much additional effect the remus/Akra/K&N is having - all a bit of guesswork.
 
Mine has done about 6000 miles with aftermarket exhausts (5000 with the Akra Ti twin can) with baffles. Its way too loud without baffles and I could detect a slight difference when they went in. Its got the standard air filter and always gets posh petrol.

Rather spend waste money on accelerator modules that are almost certainly not needed, simply call Hilltop to discuss.
 
OK

That is the original nub of this post.........I'm booked into Hilltop next month but to run 350 miles down there on a lean mixture is worrying me. I'm now thinking of putting the original filter in and getting an accelerator module on just to get me there without burning valves out.
Would that be my best option?
 
I have a standard air filter with a baffled "race" exhaust system and no IAT resistor (accelerator module).

It's done 6000 miles with so far no problems. I have had the spark plugs out and they all look just as they did with the standard catalyst exhaust. That suggests the ECU has adjusted to my exhaust setup. It would probably be ok without the baffles but my ears wouldn't.

Just use baffle the exhaust, keep the original air filter use posh petrol.

The only way to be 100% about the valves burning is to trailer the bike down. Slight overkill to my mind but the valves wont get too hot.
 
Yes, but they require re-oiling. Why bother ? What do you hope to achieve with a K & N, as opposed to an OE filter ?

The OE Paper filter starts off as free-flowing (as much as it physically - can). From that point onwards - it gets gradually more-restrictive to flow.



The K&N type - filters by holding the contaminans with the oil coating, not by physically restricting - therefore degradation over time - is minimal.

Al
 
The OE Paper filter starts off as free-flowing (as much as it physically - can). From that point onwards - it gets gradually more-restrictive to flow.



The K&N type - filters by holding the contaminans with the oil coating, not by physically restricting - therefore degradation over time - is minimal.

Al

The OE still provides more air than the engine can handle. K & N's do degrade & do allow particles through unless re-oiled frequently. Why bother ?
 


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