#6

[speedpro]

Pretty colours after four dyno runs

[jasonu]

quote Sonic-V "Any chance you could show the power curve even if against road speed? I am particularly interested to see if you actually have a double hump to your curve which would indicate some sort of recovery. "

This is exactly what I got on the dyno with the first Wobbly pipe as seen in the above post. It had what looked like a normal sort of peak but instead of falling off past that it fell a bit and then peaked again to about 75% of the main peak. Removing 40mm made it worse as well. I wasn't sure which engine Wobbly had designed the pipe for but I think now it was for the old style one which he was pretty scathing about. Pity I didn't build it in time to try on the old one as he reckoned 25hp at the rear wheel.
Anyway . . . . I tried the new laser cut pipe which I've made for the RS chassis with it hanging out the side on the dyno and it made an immediate nearly 2hp increase. The jetting was on the lean side of perfect I think and the timing was a bit advanced, things we had been trying to get the first pipe to work. Not only did the new pipe make more power but it had a good spread as well. We were in a gear which peaked at a bit over 100kmh on the dyno and the power was flat(ish) at peak for 30-40kmh, and the double hump disappeared. It ended up making 20.9hp with more to come I'd say.
The 2nd hump on the first pipe was at horrendous revs, way more than I've tried before. We tried another pipe John had hanging up but the motor didn't want to know. Another old-school pipe that resulted in a lot of crackling in the pipe at it's peak revs.

Hey Green, is that 20.9 John HP or actual 'corrected' HP? (John HP +10%ish from memory)

[speedpro]

Corrected I presume, the graph showed a smaller number and John had his calculator out before giving me an actual number.

[jasonu]

Corrected I presume, the graph showed a smaller number and John had his calculator out before giving me an actual number.

Nice going. DT said you are hauling my bike to Taupo for the GP.
Hope it doesn't blow a crank...
Good luck to you both and make sure you put it to the valve'n'camers.

[speedpro]

I'm expecting the crank to blow, it's what your bikes do at Taupo - blow cranks.

[Buckets4Me]

make sure you put it to the valve'n'camers.

I think there should be an easy 7-10 smokers that should be able to put it to the valve'n'alsorans easily (if the riders can is the next question)

[speedpro]

F5 should be able. Put him on a bike with twice the power of his 50, light fuse, stand well clear.
No pressure Dave, or for you.

[speedpro]

Just found a real nice free viewer of ".dxf" files from solid works called Solid Works E drawings 2010. I have the dxf file for my laser cut pipe but the SolidWorks program i have wouldn't display it properly. This s/w does and converts it to a number of other useful file formats such as jpg.

[speedpro]

I'm using the depression "post-TRRS" to motivate me in getting this bike going properly.

My sister-in-law Viv sorted out the individual pipe pattern pieces onto separate A4 pages but I had a problem printing them where they were each scaled differently. Skunk thought he may be able to convert them to something I couldn't stuff up and he was right. I've cut the paper patterns out and now just have to translate it onto .8mm mild steel. It is still scaled ever so slightly down but it may better match the engine in the FZR which has a smaller exhaust port. Easy to compare on the dyno once built.

[Skunk]

I can print copies for anyone else for a mere $300 - that's right isn't it Speedpro?


Yeah right!

[speedpro]

Anyone who knows Skunk should go and say goodbye, soon.

[speedpro]

Bit of progress on the pipe front. One pic shows the steel with paper attached all sellotaped up so it fits the FZR and the other two are the pipe ready for spring mounts etc. Should be able to fire it up this weekend. If this all works I'll transplant the "other" cylinder and head into the bike and sort out a radiator. I'm really looking forward to see how it goes.

[F5 Dave]

Looks like quite a Big header & makes the first diffuse section look like it blends with the header. Strong taper on the header too? Also the stinger looks big, or is that just a larger transition for an internal stinger?

Ahh heck it's hard to judge these things from pictures, maybe I'm up the cock cause the first pic doesn't look that odd.

[speedpro]

From my scribblings when on holiday a while back, this pipe has design characteristics of a peaky pipe. The header is more steeply angled than otherwise which is how the peakier designs were in comparison. Compared to my designs which had a fixed diameter centre section and a less steep later part of the diffuser cone, this pipe has a steeper late part of the diffuser and a reasonably fat centre. I may build a few straightish versions to test on the dyno. Way too much work to make curved ones just for testing. There is a precise diameter and length nozzle at the exit of the baffle cone and the pipe you see slips over it and is a couple of mm bigger.

[F5 Dave]

yep figured you'd be on to it.