Post by muttsnuts on Feb 16, 2014 11:28:54 GMT 1
Had Dave's 421 on the dyno yesterday for checking and tweaking.
The initial runs and checks showed several areas for improvement, but it was still pretty impressive producing circa 65BHP and 38ftlbs of torque.
After some changes, the bike got into the early 70's fairly quickly producing around 42ftlbs of torque.
Some time later............(after a few tweaks and changes to the set up).............
The maximum BHP was hitting around the 74bhp and 45ftlbs of torque, at this point the fueling was on the safe side and the bike was responding well, next was to have a play with the ignition timing, working through a series of settings and checks, the final max BHP was just shy of 78BHP (77.9bhp) and torque was up to 48.8ftlbs (all done by tweaking the ignition).
Apart from the impressive final figures, one of the most striking things about this engine was its ability to rev quickly, a couple of times the bike span the rear tyre on the new roller
, which required the bike to be strapped down further (that's even a first for me with a 2 stroke !)
The bike basically goes from 27bhp at 6000rpm to 77bhp at 8500rpm in 3 seconds !, that's some impressive stuff beleive me !
The bikes final settings where left with max Torque at 48.8ftlbs and 76.7BHP, the reason for knocking it back a bit was simply to bring the power in at the point it was most useable, since max power is at 8500, there is little point revving the bike higher, all that does is result in quicker engine wear and its a road bike, not a race bike, so its been tuned to suit that.
Lower down the rev range there is further work that could be done to improve it (not that its bad at the moment !), but as with all things time and money is a factor and by this point we had been on the dyno nearly 6hrs, but have gathered a whole pile of data and hopefully Dave has learnt a bit more about his bike and how it all fits together and works.
More work to be done and hopefully we will be seeing Dave's other bike in due course for it setting it and maybe we can see that one surpassing the 80BHP and 50ftlbs of torque, all mightly impressive I must say.
Before people ask, the duyno used is a DynoStar 70, and this one has just had a full factory refit and calibration done 4 weeks ago, so its as accurate as your going to get, a 12% factor was used for transmissional losses to gain rear wheel BHP, so in real terms the engine "crank" horsepower is around 87BHP.
Graphs below
BHP Graph - this shows how the bike is set up now
This graph shows the Torque (crossed hatched lines below the BHP lines)
and finally the the acceleration (Time) graph, check it out at 7 secs to 10 secs - now this is going to be a hoot to ride !!
just one final thought, to put this into some sort of perspective, Daves engine is producing more torque than a standard LC produces BHP, now that's food for thought !
Personally I can't wait to get feedback on how it rides compared to what it rode like before it was dyno'd
Oh and before anybody asks, the various settings of the bike are Dave's to share, not mine, so while I'll be happy to answer any questions you may have, information in respect of the engine I can't answer as I don't know the full spec, jetting I do know of course, plus of course a few tweaks we did (which sorry guys will remain a secret unless Dave wants to share them) and finally the ignition settings, Dave has the maps for the various tests etc we did
Onwards and upwards, nice little target for me to aim at with my Turbo !!
oh and just to add, I beleive Dave is running some of Kenny's new pipes made for producing torque and power lower down, while I have no comparison to go by, looking at the results and the vast amount of data we have, I'd have to say that they do exactly what it say's on the tin !
The initial runs and checks showed several areas for improvement, but it was still pretty impressive producing circa 65BHP and 38ftlbs of torque.
After some changes, the bike got into the early 70's fairly quickly producing around 42ftlbs of torque.
Some time later............(after a few tweaks and changes to the set up).............
The maximum BHP was hitting around the 74bhp and 45ftlbs of torque, at this point the fueling was on the safe side and the bike was responding well, next was to have a play with the ignition timing, working through a series of settings and checks, the final max BHP was just shy of 78BHP (77.9bhp) and torque was up to 48.8ftlbs (all done by tweaking the ignition).
Apart from the impressive final figures, one of the most striking things about this engine was its ability to rev quickly, a couple of times the bike span the rear tyre on the new roller
, which required the bike to be strapped down further (that's even a first for me with a 2 stroke !)The bike basically goes from 27bhp at 6000rpm to 77bhp at 8500rpm in 3 seconds !, that's some impressive stuff beleive me !
The bikes final settings where left with max Torque at 48.8ftlbs and 76.7BHP, the reason for knocking it back a bit was simply to bring the power in at the point it was most useable, since max power is at 8500, there is little point revving the bike higher, all that does is result in quicker engine wear and its a road bike, not a race bike, so its been tuned to suit that.
Lower down the rev range there is further work that could be done to improve it (not that its bad at the moment !), but as with all things time and money is a factor and by this point we had been on the dyno nearly 6hrs, but have gathered a whole pile of data and hopefully Dave has learnt a bit more about his bike and how it all fits together and works.
More work to be done and hopefully we will be seeing Dave's other bike in due course for it setting it and maybe we can see that one surpassing the 80BHP and 50ftlbs of torque, all mightly impressive I must say.
Before people ask, the duyno used is a DynoStar 70, and this one has just had a full factory refit and calibration done 4 weeks ago, so its as accurate as your going to get, a 12% factor was used for transmissional losses to gain rear wheel BHP, so in real terms the engine "crank" horsepower is around 87BHP.
Graphs below
BHP Graph - this shows how the bike is set up now
This graph shows the Torque (crossed hatched lines below the BHP lines)
and finally the the acceleration (Time) graph, check it out at 7 secs to 10 secs - now this is going to be a hoot to ride !!
just one final thought, to put this into some sort of perspective, Daves engine is producing more torque than a standard LC produces BHP, now that's food for thought !
Personally I can't wait to get feedback on how it rides compared to what it rode like before it was dyno'd
Oh and before anybody asks, the various settings of the bike are Dave's to share, not mine, so while I'll be happy to answer any questions you may have, information in respect of the engine I can't answer as I don't know the full spec, jetting I do know of course, plus of course a few tweaks we did (which sorry guys will remain a secret unless Dave wants to share them) and finally the ignition settings, Dave has the maps for the various tests etc we did
Onwards and upwards, nice little target for me to aim at with my Turbo !!
oh and just to add, I beleive Dave is running some of Kenny's new pipes made for producing torque and power lower down, while I have no comparison to go by, looking at the results and the vast amount of data we have, I'd have to say that they do exactly what it say's on the tin !
,might get 70 with a Zeel but that's about it unless you go big bore I guess 
