I have fitted an Akrapovic Slip-On Line Anniversary Edition to my 2013 Blade, looks great and sounds beautiful but here is my problem. Slight flat spot at about 2900 rpm (Which I can live with) but on overrun you get engine braking until 4000 rpm where it fills as if you've open the throttle slightly and now no engine braking :-( Things I've tried:- 1. Reset the ECU. 2. Adjusted the flap cable which should be around 46mm pulled out but the closest I can get is 52mm before running out of adjust. I don't want to start putting a Power commander on as I'm thinking of getting the 2014 SP model and swap this exhaust onto it but want to sort the problem out before I do using this bike as a test piece. Have spoken with local Honda dealer and they had the same problem when they swapped one from 08 Blade to 12 Blade but then customer just stuck with stardard one on and sold Akrapovic. Can anyone please help or could it be down to this cable adjustment for the flap?
I have the non cat version on my 13 no issues at all ? Do they sell or have a race link pipe ? See if that helps ?
Also is that problem with the baffle out by any chance? Without a PCV I find they runner better with the baffle in
It's not the exhaust. I have this problem with my 2012 anniversary model and it is completely standard, had it from new.
The Akra Anniversary edition exhaust has all the CAT shyte in it which is why they were on offer earlier in the year cause no fecker wanted them compared to the full Fat Akro units. I suspect the CAT internals are not indentical to the OEM Zorst hence the flat spots etc. Mines standard and has none of the above problems. Any exhaust change should really have a Powercomander and custom map for spot on fueling.
Thank you for all the replies, baffle is still in and my thought was putting the one with CAT and FLAP would mean no farting around with fueling, oh well :-(
I have a 'full fat Akro' (Complete System) without the CAT shyte and I don't have any flat spots but do get a very slight surge at 4K on overrun. For me it's not an issue at all and I wouldn't consider it a problem by any stretch. I haven't had to adapt my riding or ride around it all it does is tell me I'm at 4K without looking at the dash.
That's it "Mr B" the surge at 4000rpm, just like opening the throttle ever so slightly, strange. Will have to see what happens when I fit it to the SP next year.
Personally i think the blade has too much engine breaking anyway so appreciate it at that narrow rpm and enjoy! Its the one thing about the blade which i dislike to the point of anger - it makes throttle on/off transitions too harsh. I believe this was something honda tried to fix on the 13+ on bikes and perhaps this is a result of some honda ECU fettling... dunno. Arthurbikemad is your man to ask.... Interestingly i recently ran an Autotune on my blade (11 with full fat Ti Akra) and really liked it - a custom map is great, but the autotune will take into account atmospheric differences year round and geographical changes (altitude/air thickness)
All blades have the problem/issue if you ask me (I.e too much) just some people don't notice it so much, I was told that Alex Lowes had the same problems and was one of the issues he suffered with the bike this years and to blame for some of the offs, seems no matter how hard they tied they could not fully map it out. I find mine the same even though a totally different year/model, I fitted the Sigma to mask some of the harsh deceleration but sadly the transition to open throttle is still an issue for me, fine in a straight line but mid corner it's unnerving, not having enough engine braking is quite the other way round from the problem most face, some teams have complex software to manage the exhaust valve and control engine braking, thanks to the PR over this years racing people now look at ALL flappers in this light, they read too much into what's being said in WSB as most are just for noise control, the effects of engine braking in that system are unknown and get confused with those used in racing.
Isn't the surge you're feeling when the PAIR valve sticks a little fresh air down the pipe to help save the planet
Not sure about PAIR valve but as I'm getting the SP next year lets see what happens when I shove the Akro on it!
Pretty sure the pair valve won't make any difference to the engines braking capabilities, the pair system introduces filtered air from the airbox into the exhaust close to the exhaust valves in the cylinder head, this air mixes with any hot unburnt fuel mixture in the exhaust. This increase in air allows this fuel mixture to ignite and allowing more poisonous gasses to be burnt rather than expelled into the atmosphere. The ignition of these gases have no baring on the engines power output as the fuel burn happens in the exhaust (often causing audiable popping during decel) burning out towards the atmosphere and not in the engines cylinders. The use of the exhaust flap is different as it can be used to basically block the exhaust off to provide back pressure to the engine making it harder for the engine to expel all the gasses out the cylinders during the blow stroke of the engine.
Just a thought but all them little explosions in the down pipes would put a little positive pressure back into the head when the exhaust valves are open would they not ? Less scavenging from the head / maybe a little boost in power / less engine braking I am just hypothesising and have no training in this area .... it's just there's nothing good to watch on the TV
I know where your coming from NT but I am more inclined to say no the small explosions in the exhaust would all head out the rear of the exhaust as its the way of least resistance, when the exhaust valves are open there will be exhaust gases being pushed out into the headers and exhaust to make way for the next bang in the cylinder and again those exiting gasses should find it easier to head down the pipes and out the rear of the pipe into the atmosphere. Where as the exhaust flap valves physically close of the exhaust making it harder for the gases to go out the rear of the exhaust leading to a back pressure building up when the exhaust gasses are getting pushed out from the cylinder head.
Ahhhh but pressure waves can move back against the flow of gases , burnt or unburnt . Think thats the principle of the expansion pipes on a 2 stroke - a reverse pressure wave to slow the gases from the head . touche , have a thee varlet
Power pulses, an exhaust design is highly complex it takes into account gas flow and sound waves, shock waves must leave the system and not rebound back into the combustion cylinder, make me chuckle when Akra spend hours developing a system and then someone cuts it down...lol Oh hang on, I cut one of mine down, yeah, but that's for show and not for go
I always go with Akrapovic as you can be assured the amount of R and D they put in is amazing, plus resale value is good as it's such a quality product Shame I can't shift the CB1000R one I have sat in the garage though
Ok i aint no exhaust designer and probably dont know the half of what goes on in there but aint one of the main reasons for fitting aftermarket exhaust such as the akra to reduce back pressure and increase flow out the back? Oh that and they sound brilliant! The pair valve also only draws air when there is a drop in pressure in the exhaust so any build up of back pressure in the exhaust would stop the pair from working. It's also meant to be there to help supply enough oxygen for the catalyst to work correctly on the exhaust gases.
