Man Day at the Dynos - ZRX Edition

I won't bother repeating the Dyno Day setup as it is all in the previous Fizzy dyno post. Needless to say, I had no preconceived notions as to what I expected out of the Fizzy for horsepower and the 150hp pull was a nice surprise. As for the ZRX, well that is a whole different story. You guys have listened to me complain about my ZRX over the last year and given that I pulled the numbers I did on the ZRX, I feel the majority of my issues probably revolved around the coil wire that was working during the same time frame. Although I had fixed the coil wire issue on the ZRX and confirmed it ran, I only took it around the block and never ran it hard before getting the Fizzy and putting the ZRX into hibernation. I can't help but think my ZRX was not running as it should have been for months prior to me finding/fixing the coil wire issue and that reinforced some of the negative feelings I had for the bike based on the pitted Muzzy cams and my "imaginary" pinging issues. In any case, you can see from my post documenting my return to the ZRX World, the bike is running stronger than ever and I am extremely pleased with it!

Back on topic, the first pull on the ZRX showed 142hp with an A/F above 15. Bike was so lean it was shooting flames out the exhaust which you can see in the video and really popping on decel. Driveability on the street was good but I was definitely running too lean. As dyno runs were only $20, Dick and Brett suggested we rejet the bike to see what kind of difference we could make going from 135 to 138 mains. Brett ran me to the house in his truck, we picked up all the tools needed and rejetted in the parking lot. I paid for another run and the dyno operator was confused as to why I wanted to run it again. I explained we had rejetted the bike and wanted to see where A/F was at. He seemed duly impressed! Second pull netted a solid 147hp with A/F still being well above 14. At Dick's suggestion, I will come out on the air screw 1/4 turn next time I have the carbs off but I think going up any more on the mains will kill my driveability and mileage. Also, a little lean in Tulsa would only fatten up as I gained altitude in Arkansas so all in all, I think I'd prefer to be a little on the lean side. I'd love to hear anyone's thoughts on the subject.

Maybe it was just my imagination but the bike seemed peppier on the way home and I am looking forward to getting it out where I can really "wick it up"! Looking at the power curve of the second dyno run, I think it explains pretty clearly why we all love the ZRX so much. Overlay that power curve over the Fizzy power curve and there isn't even a question as to which bike would be more "fun" to ride. All in all we had a great time and I feel I got my money's worth for the $60 I spent. It was nice to spend the day with my friends and a bunch of motorcycle guys standing around watching dyno runs like they were a burlesque show. There were some pretty sick bikes out there with one guy trailering his drag bikes from Fayetteville to take advantage of the dyno. Enjoy the videos and pics!














Fizzy on the dyno...


ZRX on the dyno...


How to rejet a ZRX in 7 mins...


Always willing to help...


Contrary to popular belief, I am capable of doing
some things on my own...


Lots of friendly folks around...


Sonny Crockett stopped by...

Man Day at the Dynos - FZ1 Edition

A local bike shop, Metric Cycles, had an "End of Summer" bash on Saturday at which they were offering $20 dyno pulls. I thought this would be a great opportunity to get the Fizzy baselined for horsepower and also, I hadn't had the ZRX officially dynoed since I added the hi-comp pistons and cams so was excited/nervous to get that done. I invited a few folks to join me and Dick, Brett and I headed up to the shop arriving right at 10:00am, Dick on the Fizzy, me on the ZRX and Brett in his truck. Dyno runs were from 11:00am to 2:00pm and I was just sure bikes would be lined up in the streets for the bargain dyno runs and I wanted to get in line so we would be sure to get a pull. Well, I guess the rest of Tulsa wasn't quite as excited as I was and Dick, Brett and I were the first 3 people to show up. Fortunately there were donuts and coffee available and we sat around for a while catching up and talking motorcycles. After "breakfast", I got both bikes signed in and paid for and we rode around back to the dyno which was loaded with a beater V-Max that was just finishing a wicked 90hp pull. As much as I lusted over the V-Max in the late-80s, they seem to disappoint every time I see one on a dyno!

As we were the only bikes there, the Fizzy immediately went on the dyno. Now I really had no idea what to expect as I had read so many different things on the Fizzy board concerning various mods and expected horsepower. All I have done to the Fizzy performance wise to this point has been to add an Akra slip-on I got from Scott Vint for $300 shipped, install Ivan's Fuel Cut-Off Eliminator for about $100, gutted the catalytic converter in the mid-pipe along with opening up the airbox. Collective wisdom on the FZOA says these mods require a power commander lest "extreme damage" be inflicted on the engine due to an exceptionally lean A/F ratio. "Danger, Danger!". Well, although I had intended to pick up a Power Commander at some point just to get to play with custom mapping, I almost pulled the trigger as soon as I found out about the dyno day thinking I would need it to make maximum horsepower. As you can see from the dyno chart below, that would have been an exceptional waste of money and I may still buy one but it is by no means "required".

The other guy in the video, assisting the dyno operator, is Brad and is someone I have dealt with before as he mounted my last set of Diablos for me. Interestingly enough, it turns out he has an '07 Fizzy as well but his is bone stock but more on that below. Once the Fizzy is secured on the dyno, the operator brings the bike up to speed and pulls some baseline readings. After his first full pull, I notice him glance over at Brad giving him a strange look. Although I can see the dyno monitor, I can' really tell what is going on but fear the A/F might be so out of whack that the operator is concerned to pull again. That turns out not to be the case as the operator executes another couple of pulls. As the operator finishes the run, Brad steps up to the operator who says something that I can't quite hear and to which Brad responds with a blank look. At this point, all I am thinking is that either my A/F is way out of whack or my bike has just pulled some really pathetic numbers and they are trying to decide how to break it to me. Neither is the case and the brief exchange between the operator and Brad is due to the Fizzy just pulling 150hp! The look on Brad's face was actually surprise as he had just dynoed his bike at 133hp! Cool! See video below and then dyno chart below that.

Embedded video hint: Start video then hold down the CNTRL and ALT key and then click anywhere in the video window again. This will take you straight to the Youtube version where you have access to video info and High Quality setting.

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