Post by Soupdragon1957 on Jun 21, 2011 6:25:47 GMT -5
After a bit of a saga with air filters I finally came to the conclusion that I might as well fit pods & ordered a set of 15 deg angled intake (snowmobile) uni's. Bike has stock pilots (22.5) & 92.5 mains, there was a slight blubber at 5000 rpm which I tuned out by dropping the needles one notch from centre. With this set up the bike runs clean with zero bogging, blubbering, flat spots, or hesitation & pulls strong all the way to the red line.
Once 'on the pipe' at 6500 - 7000 it pulls really hard & my butt dyno told me it was working way better than when I had the Wirges fitted. The WTF's continue producing power where the Wirges start to tail off as the needle approached the red line.
I had some correspondence with TTNut who was kind enough to give me some numbers from his pipe design software, I threw these into MS excel & produced a chart.
The chart shows the RPM / HP comparison between the WTF & Wirges pipes. Anyone who has tried both setups will be able to confirm with their butt dyno what the chart shows.
I though it would be cool to see if a real dyno run produced a similar curve / data set to the pipe design software. I also of course was curious to see how the power produced stacked up to Kawasaki's original 42 Hp claim. Lastly, but most importantly I wanted to see how good my carb set up was to make sure the motor would be safe at higher rpm.
So, with this in mind I finally bit the bullet & booked a baseline run with Craig at CyclePro. As some of you may know Craig is a board member & has a lot of knowledge on tuning triples, he also looks after the wrenching & tuning of Gary Connors H2 drag bike motor.
Craig was also kind enough to allow me to watch the dyno runs and take pictures & video of the run which proved to be very interesting & also produced better results than my pessimistic (realistic?) nature predicted. Craig asked me how high he could rev the engine & I told him 9000 rpm, as things transpired this was a bit optimistic..
After a few set up tweeks the first run produced 38.8 RWHP, (my prediction was 30). I should add that my prediction was based on a dyno chart I saw back in the day which said 28 RWHP. maybe someone has a copy of that chart they could post?
Anyway, Craig explained that he did not take the bike to the red line because he could see that the motor was getting into a little distress at high rpm. he surmised that this was likely due to the mains being either too rich or too lean, but More likely too lean.
To prove his theory he employed an old school trick (which was new to me) of partially taping off each intake filter with duct tape. The effect of this is to restrict airflow & therefore richen up the mixture.
The next run produced 40.3 RWHP, still signs of distress at high RPM but proof that the mains are too lean. Based on his experience Craig suggested going to a 97.5 main jet which should give the motor the gas it needs at high RPM & will likely improve the peak HP further.
The Dyno chart shows a small dip in the power & torque curves around the 5000 rpm range, something he concluded is likely the pipes, interestingly this dip is also shown on the date supplied by Don. Looks like we have correlation between theoretical & actual data, something us engineers always like to see..
Needless to say I'll be ordering a couple of sets of jets from Ellen later today to see if it cleans up the top end a bit more. perhaps when I'm feeling rich one day I'll have Craig do another run to see how the power looks..
Click to run video..
SoupD.
Once 'on the pipe' at 6500 - 7000 it pulls really hard & my butt dyno told me it was working way better than when I had the Wirges fitted. The WTF's continue producing power where the Wirges start to tail off as the needle approached the red line.
I had some correspondence with TTNut who was kind enough to give me some numbers from his pipe design software, I threw these into MS excel & produced a chart.
The chart shows the RPM / HP comparison between the WTF & Wirges pipes. Anyone who has tried both setups will be able to confirm with their butt dyno what the chart shows.
I though it would be cool to see if a real dyno run produced a similar curve / data set to the pipe design software. I also of course was curious to see how the power produced stacked up to Kawasaki's original 42 Hp claim. Lastly, but most importantly I wanted to see how good my carb set up was to make sure the motor would be safe at higher rpm.
So, with this in mind I finally bit the bullet & booked a baseline run with Craig at CyclePro. As some of you may know Craig is a board member & has a lot of knowledge on tuning triples, he also looks after the wrenching & tuning of Gary Connors H2 drag bike motor.
Craig was also kind enough to allow me to watch the dyno runs and take pictures & video of the run which proved to be very interesting & also produced better results than my pessimistic (realistic?) nature predicted. Craig asked me how high he could rev the engine & I told him 9000 rpm, as things transpired this was a bit optimistic..
After a few set up tweeks the first run produced 38.8 RWHP, (my prediction was 30). I should add that my prediction was based on a dyno chart I saw back in the day which said 28 RWHP. maybe someone has a copy of that chart they could post?
Anyway, Craig explained that he did not take the bike to the red line because he could see that the motor was getting into a little distress at high rpm. he surmised that this was likely due to the mains being either too rich or too lean, but More likely too lean.
To prove his theory he employed an old school trick (which was new to me) of partially taping off each intake filter with duct tape. The effect of this is to restrict airflow & therefore richen up the mixture.
The next run produced 40.3 RWHP, still signs of distress at high RPM but proof that the mains are too lean. Based on his experience Craig suggested going to a 97.5 main jet which should give the motor the gas it needs at high RPM & will likely improve the peak HP further.
The Dyno chart shows a small dip in the power & torque curves around the 5000 rpm range, something he concluded is likely the pipes, interestingly this dip is also shown on the date supplied by Don. Looks like we have correlation between theoretical & actual data, something us engineers always like to see..
Needless to say I'll be ordering a couple of sets of jets from Ellen later today to see if it cleans up the top end a bit more. perhaps when I'm feeling rich one day I'll have Craig do another run to see how the power looks..
Click to run video..
SoupD.
