mikstr

thanks for the reply.

you dont have to drill into the actual carb body I hope as I am a bit leery about shaving ending up in the carb adn really screwing things up.

In terms of your results/first impressions, was your bike stock before or was it already jetted? Also, did you get the accessory filter kit for it?

cheers
Mikstr

killer5280

No drilling is required. The drill bit is for drilling holes in the airbox. My bike had slipons, shimmed needles and one size larger main jets before the FC. I'll have it dynoed in the next week or so and we can see how much improvement the FC made.

AZZKIKER

How much did it cost?

killer5280

135 bucks.

AZZKIKER

Let's see some dyno pulls and then i will decide. I might buy it if it shows good results.

mikstr

any dyno results (or seat of the pants for that matter) to report?

cheers
Mikstr

killer5280

I have been trying all week, but for one reason or another I have been unable to get the bike to the local dyno. I think I'm going to make it this afternoon.

The seat of the pants impressions remain the same; better throttle response and more midrange kick, while top end power seems about the same. As soon as I get the dyno charts I'll post them here.

mikstr

thanks

Looking forward to seeing (or hearing about) the dyno results.

cheers
Mikstr

killer5280

I had the bike dynoed today. We did 3 pulls and adjusted the airflow screw for each run. The first run was waaaay rich and was worse than before the Flo-Commander. For the second run I leaned out the mixture and it was much better. The curve was slightly above (1 to 2 hp) the dyno run I did a couple of weeks ago all the way from around 4000 to redline, with a peak horsepower advantage of about 1.5 hp. (I'm typing this from memory.) The third run I leaned it out even more and the overall curve wasn't as good as the second run, but peak power was a little better; however, this run was only better than the stock run from 7000 to redline. Unfortunately, the chart they emailed me is the third run. I'll get the other graphs from them tomorrow. They also didn't send a graph with torque figures, but I'll get that too.

Overall I'm a little surprised at the results. The throttle response and jump in the midrange led me to think that I would see more power gains in that part of the rev range. Also, the flat spot on the dyno chart was almost unchanged, but it sure doesn't feel like it when riding the bike. I didn't expect to see a 2 hp increase at the top as seen in the chart on this post.

The Flo-Commander does allow quite a range of adjustment and it does sync the carbs together better, which is why it feels so much better in the throttle response department. With more dyno time I'm sure more improvements could be made, but I have more mods coming and I'll dyno it when I'm done with those.

AZZKIKER

MMMM. I think I will save my 130$. Thanx for all the hard work though. Saved us a lot of work. Let us know if anything changes.

killer5280

Oh yeah. While I did see some worthwhile improvements in power and drivability, not to mention the overall ease of carb adjustment with the FC, the improvements I saw are nowhere near as dramatic as those on the dyno chart on the first page of this thread. Maybe it's the K&N filter on that bike. Yeah, that's the ticket. :wink:

killer5280

AZZKIKER wrote:

I'll keep you updated. It does improve things, but does it improve them 130 bucks worth? Maybe.

killer5280

Here's the graph for the second run we did yesterday, which is better than the one I originally posted. It looks like they didn't apply the correction factor, so the figures are higher than the other graphs, but run #7 definitely is the best of all with more power all the way through the range.

mikstr

Realistically you won't be chasing down any R1's with the increase

However, if it does make the engine smoother and more responsive (two important considerations for me, more so than an additional hp at 9000 rpm) and yields a slight increase across the board (not to mention adjustability for temp and altitude), it may be worth it. After all, what do you expect for $130?

thanks for sharing

Mikstr

killer5280

Your thoughts are pretty much in line with mine. Although it does show some definite gains, although not earth shattering, the most noticeable benefits can't really be seen on a steady throttle dyno run. The bike is definitely more reponsive to throttle input and more fun to ride.

I think more improvements can be made with jetting changes. I have an extra set of heads on which I'm having a valve job and port work done, along with a set of cams. I'm also going to see about bumping the compression a bit without resorting to aftermarket pistons. I'll keep you posted.

shayne

I have done a piston swap to raise the comp in my engine. I spoke to a guy here in Oz who has done a lot of development work on VTR's, and his advice was not to look for a comp rise by machining the heads or cylinder. This will lead to even more dramas with the cam chains than we have already, due to increasing the slack in the chain, which we don't want.

The other option other than pistons is to re-work the combustion chamber. I would think pistons would be a cheaper, and better option, as the chamber look ok to me, and I wouldn't want to change them.

By the way I used American made pistons, made by CP. Honda wants $450.00 AUD, and the CP's were $660.00 AUD at any compression ratio you wanted. Good value I think, and nicely made.

killer5280

Thanks for the advice Shayne. I plan to proceed very cautiously.
The piston kit that gets the most mention around is from JE pistons, which bumps compression to 11.5:1 and costs about 250 USD.

mikstr

Hi killer,

just wondering what setting (no. of turns out) gave you the best results (and, for reference, what was the ambient temperature?).

I set mine as per the directions at three turns out (supposed to give you pre-FC results) although it is quite cool here as it is early Spring. Also, what did you find in terms of the effect of the screw settings in jet size equivalents (eg. 1/2 turn = @ one main jet size, for example). I have no immediate plans to run mine on the dyno in the near future (although I may do so when the weather warms up) so I was hoping you could shed light on this matter.

cheers
Mikstr

killer5280

2.5 to 3 turns out gve me the best results on the dyno with the main jets I have, which are, I believe, 185 rear and 182 front. This is also where I had set the screw from my seat-of-the-pants impressions. It's hard to say how much each turn of the screw affects jetting in terms of main jet size because the FC affects mixture over such a broad range and all throttle settings. The synchronizing effect is stronger the leaner you run the screw on the FC because of the greater air flow through the FC setup, so it's better to be slightly rich on the jetting and lean it through the FC. I would suggest starting rich (1 turn out), riding for awhile and then leaning the mixture 1 turn at a time until it feels best. It wasn't hard for me to tell when it was way too rich or lean.
I can't remember the ambient temp when I did the runs, but it was cold. I would guess around 45 degrees or maybe even a little cooler.

killer5280

By the way, I bought a spare airbox on eBay and was surprised when it came with a used K&N filter. I cleaned and oiled the filter and stuck it in my bike. The bike would hardly run at all. It was so lean that I could only use partial throttle most of the time and it wouldn't pull to redline. It was so bad that I didn't spend much time trying to tune it. I'll try it again sometime when I feel like playing with the jetting.