ESE's works engine tuner

[F5 Dave]

Well I had another fairly depressing day at the dyno. Despite the rebuild I was 1hp down & at narrowed spread & increased revs. Odd. Did the EGT probe effect the pipe? Would have been useful if I'd taken the bung with me but sadly forgot.

Also I kept throwing mains at it as in all gear runs it was falling off at the upper gears. It liked it & I'd gone from a 130 to a 142 before it went a smidge too far.

Maybe it has an airleak. I'll do a pressure leakdown test.

So how long has it been like this is also a question? maybe I was running the last GP like this as I never retested it after that rebuild & I've run the bike so infrequently after my crash.

Best look under the seat, maybe it's there.


So what did I learn from, the EGT? Hmm I need more time on it. it reacts very swiftly. Thinking back it was kinda queer as it was getting hotter with every gear. OK it was falling off power as slightly lean. But this should have shown the temp get hot & then cooler. But this didn't happen.

[TZ350]

.

Was 20 rwhp at 11,250 RPM now 21.5 RWHP at 9,000 rpm BMEP 8.5Bar, SS90 was sure right about unmasking the transfers and Sonic-V’s tips on diffuser carbs sure have made a difference.

But from the numbers my RS pipe at a TL of 825mm is short way to short as Blair suggests a TL of 1045mm for this scenario.

At 11,500 rpm the pipe will be the right TL and if I can get the same or better BMEP then I can expect a handy increase in RWHP.

Going for the max………

.

[sonic_v]

.

Was 20 rwhp at 11,250 RPM now 21.5 RWHP at 9,000 rpm BMEP 8.5Bar, SS90 was sure right about unmasking the transfers and Sonic-V’s tips on diffuser carbs sure have made a difference.

But from the numbers my RS pipe at a TL of 825mm is short way to short as Blair suggests a TL of 1045mm for this scenario.

At 11,500 rpm the pipe will be the right TL and if I can get the same or better BMEP then I can expect a handy increase in RWHP.

Going for the max………

.

Nice to see things moving the right direction!

Any chance of showing either a torque or bmep curve?

[TZ350]

Well I had another fairly depressing day at the dyno. Despite the rebuild I was 1hp down & at narrowed spread & increased revs.

I have had them too, and if the results aren't depresing then they are more often than not just confusing.

I am making another cylinder to better match the pipe, fingers crossed that it works.

.

[TZ350]

Any chance of showing either a torque or bmep curve?

Will have to go to a different dyno for that, probably not before Xmas. every thing is insane around hear at the moment.

[speedpro]

Nice numbers, especially at those rpm. I got to find at least another couple. How did you measure the rpm?

[TZ350]

How did you measure the rpm?

Worked backwards from the road speed and wheel rolling diameter. So not totaly sure about the rpm but expect it's in the ball park.

.

[TZ350]

Just out of interest, what sort of ignition timing worked best.

Thomas has just put a degree wheel on it and it works out at 16 deg or 1mm BTDC.

.

[sonic_v]

Will have to go to a different dyno for that, probably not before Xmas. every thing is insane around hear at the moment.

If you are handy with spreadsheets you could pick a few points of your power/speed curve and create a chart.

[SS90]

All this talk of EGT's is quite interesting.

Kiakaha mentioned that most Kartsporters don't use them anymore, and instead use det sensors, which is interesting.

Personally I use both a Det sensor and an EGT, combined with a cylinder head temp sensor.

All the sensors have a data logging capability, which I believe is what is really needed.

I also don't really use them too much on the Dyno, as too many variables come into play on the track (atmospheric pressure for one), but when I try drastically new things on an existing engine I certainly do, simply for comparisons with previous runs on the same engine.

Interesting that you found the best power for a fixed ignition was 16 deg Teezee, when dealing with a fixed ignition, I have found that is pretty much the same.

Now is the time to make your programmable ignition!
What I notice F5dave has mentioned is that he found the temperature to be to variable to make a measurement, and I guess that would be true unless you had a data logging capability so that you could concentrate on maximum's rather than fluctuating numbers that confuse the issue.

2 years ago I went to the effort of finding Maximums (well, for air cooled two stroke small frame Vespa's that is), and I was quite surprised.

In summary of that, I found that the best power was achieved when the Maximum temp was 460 deg, and disaster was achieved at 610 deg (3 times)

However, I run lower cylinder head compression ratios and a different cylinder head design than Teezee, so th enumbers would be different than Teezee would expect.

I feel it was worth it, as it suggested that settig an engine up to run high EGT's was detrimental, not only in power, but obviously also in reliability.

I always champion the idea of "to finish first, first you must finish", and my experience suggests that a larger safety margin is best for all.

There are heaps of data logging equipment available, and the best place to look is Kartsport....... you can buy an "all in one" unit (EGT,DET, and CHT) for a surprisingly acceptable amount.

I brought mine second hand for €250 and have used in trouble free for over 2 years.

[TZ350]

Hi SS, interesting post. thanks for your ideas on the safe exhaust temperatures. Yes data logging would be very useful, we will go there in the new year.

We now have a programmable ignition but have run out of time to properly fit it and get it set-up before Taupo so that will have to wait until the new year too. Flat out just trying to get the bike to run decently as it is.

One of our 20rwhp bikes went pretty well at the BOB until an engine mount broke, I have been told that it had the legs on the CBR150 and all the FXR's which is pretty satisfying as top speed is all about overcoming air resistance with hp and aerodynamics and very little to do with weight although the light weight RS chasis would certinly have helped coming out of the corners.

As we are now developing a new generation of 20+rwhp engines, next year looks very interesting. Thanks for your help.

.

[TZ350]

If you are handy with spreadsheets you could pick a few points of your power/speed curve and create a chart.

Good idea, I am planing on getting back to John Conners dyno on Friday and will bring a hp/road speed graph home with me and see if I can convert it like you suggest.

.

[TZ350]

These are the specs of Avalons Team ESE's BOB Suzuki GP125 20 rwhp engine:

Skim the barrel 1.5mm and “o” ring it, no head gasket, thin alloy spacer plate under the barrel and Suzuki RG250 pipe modified to RM125 specs, KX80 ignition. Raise the exhaust to open 83 deg ATDC, and widen to 70% of the bore, cut 30 deg from the closing point of the rotary disk, so inlet opens 145 BTDC and closes 85 ATDC. Champher the inlet side of the crank at 45 deg to aid inlet flow. Set the mj about 102.5 105 107.5 and ignition timing, 26-28 BTDC using a dyno. A link to Bells book and the RM pipe specs can be found on page 100 of this thread.

Cheep easy effective mods that most anybody can do and get 20 rwhp.
.

[koba]

These are the specs of Avalons Team ESE's BOB Suzuki GP125 20 rwhp engine:

Skim the barrel 1.5mm and “o” ring it, no head gasket, thin alloy spacer plate under the barrel and Suzuki RG250 pipe modified to RM125 specs, KX80 ignition. Raise the exhaust to open 83 deg ATDC, and widen to 70% of the bore, cut 30 deg from the closing point of the rotary disk, so inlet opens 145 BTDC and closes 85 ATDC. Champher the inlet side of the crank at 45 deg to aid inlet flow. Set the mj about 102.5 105 107.5 and ignition timing, 26-28 BTDC using a dyno. A link to Bells book and the RM pipe specs can be found on page 100 of this thread.

Cheep easy effective mods that most anybody can do and get 20 rwhp.
.

Should go good with Avalon on it!

[gav]

One of our 20rwhp bikes went pretty well at the BOB until an engine mount broke, I have been told that it had the legs on the CBR150 and all the FXR's which is pretty satisfying as top speed is all about overcoming air resistance with hp and aerodynamics and very little to do with weight although the light weight RS chasis would certinly have helped coming out of the corners.
.

Funny that, can't recall the bike ever being in front of the CBR150?
Oh, and that CBR150 won a 150 Streetstock race too! And a standard FXR ran inside the top 10 of the 150SS too.

I think the secret is having super fast lightweight riders.