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Should i be disappointed ?

1061 Views 13 Replies 6 Participants Last post by  DirtieGirtie
so i have had the bike a year and a bit and love it no matter what .. i have spent a fair few quid on it and done most mods including performance mods ..
the bike as it stood a few days ago had standard pipes that were cut and debaffled 13 inches cut off and welded, side mounted k+n type air filters, 02 sensors removed and pair system completely removed and block plates installed ...

i put a PC5 on it and had it tuned on the rolling road when i cut the pipes .. a day or two ago i fitted Freedom Performance sharp curve pipes and had it tuned for the pipes and i picked the bike up tonight and rode it home about 20 miles ..

the tuner said i lost a few horses and torque but i gained a whole lot of small gains down low and mid throttle
.. the bike feels lovely and smooth smoother than before and i can defo feel the low and mid range settings being different but i can't help but feel a bit disappointed about losing some of what i had if that makes sense ...

here is the graph red is before and blue after .. what do you guys think ?
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We usually see between 112 - 115 hp with freedom sharpe curved radius exhaust and a modest tune.

Was the blue run shown the only run you have graphed with the new pipe and tune.
That run a looks like it may have been a bit off for some reason, torque and hp intersect at 4700 on that run.

Also I noticed you say you have a PC5 in your post but the dyno graph shows you having a PC FC.
I have not looked at the maps for the PC FC but most of this dial in type tuners with the 3 or 4 pots usually have maps with coarser scaling.

BCS
LGB/FJB
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We usually see between 112 - 115 hp with freedom sharpe curved radius exhaust and a modest tune.

Was the blue run shown the only run you have graphed with the new pipe and tune.
That run a looks like it may have been a bit off for some reason, torque and hp intersect at 4700 on that run.

Also I noticed you say you have a PC5 in your post but the dyno graph shows you having a PC FC.
I have not looked at the maps for the PC FC but most of this dial in type tuners with the 3 or 4 pots usually have maps with coarser scaling.

BCS
LGB/FJB
defo a PC5 mate ... the graph is what he gave me but he showed me on the screen all the different throttle positions and the small differences the new tune made ... don't get me wrong i like the way the bike is running but i hate it that i know it could be better ... what is a PC FC ?
just thinking about the PC5 .. it might be a PC FC because he supplied it and i fitted it so to be fair i don't really know what's on the bike ...
We usually see between 112 - 115 hp with freedom sharpe curved radius exhaust and a modest tune.

Was the blue run shown the only run you have graphed with the new pipe and tune.
That run a looks like it may have been a bit off for some reason, torque and hp intersect at 4700 on that run.

Also I noticed you say you have a PC5 in your post but the dyno graph shows you having a PC FC.
I have not looked at the maps for the PC FC but most of this dial in type tuners with the 3 or 4 pots usually have maps with coarser scaling.

BCS
LGB/FJB
Something is screwy there , if torque and horsepower don't cross at 5252 , the numbers are skewed. The only times I have seen this is when the tuner tries to fluff up the numbers on the chart for the customer , but these are lower.
so what do you guys think then ? could the tuner have done better ?
so what do you guys think then ? could the tuner have done better ?
The highest possible numbers aren't necessarily the best power or best usable power. There is something wrong with that graph making it worthless , 5252 is part of the calculation , torque and horsepower ALWAYS cross at 5252 RPM , your after does not. IF the air/fuel ratio is indeed actually what the graph at the bottom shows , you should be pretty good , but the peak numbers shown mean nothing. I hope you didn't pay the dyno boob much though.
cheers Joe .. i have been a mechanic most of my life but i know nothing about how to tune a bike on a dyno .. 5252 means nothing to me and i must admit all i'm interested in is the bike fueling correctly .. like i said before the bike feels smoother this time but i'm a sucker for wanting more if it's there so this might not be the end of my tuning adventure ...
BASS 666, if the bike feels good to you I wouldn't worry about the numbers. They might make it better if they tuned it again, or it could get worse. I care way more about how the bike feels in performance than I do in numbers.

Dyno's measure torque, then a mathematical formula is used to convert it to horsepower. 5252, as Joe said, is where the horsepower and torque lines on a dyno chart should cross.
The formula for converting torque to horsepower is: Horsepower = (Torque x RPM) divided by 5252. That's where the 5252 comes from.
For sure something is off with the blue run on that graph.
Hard to say exactly what, but something is a miss.

Just have a look at the PC and it will say right on the front of it PC-V or PC-FC.
Also the PC-FC should have 3 or 4 pots on the front it that can be manually adjusted.
The PC-V will not.

BCS
LGB/FJB
I'm with the other guys....Torque and hp don't meet at the right rpm on the blue trace....something's not right there....they should definitely meet at 5252 rpm.

Smithy.
ok guys thanks ... i might have a word with the tuner and see what he says ...
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had a look guys and it is a PC FC on the bike ...
I think your graph is good. The graph uses different scales for hp (left y axis) and torque (right).

If you ignore the visual aspect of expecting them to cross at 5252 and just compare the values at 5252 then I think that red torque = red hp, and blue torque = blue hp at 5252 tpms.
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