Time for some muscle

[06VMAXIMUS]

I mean, what were the afr #'s? For example, some call 13.2:1 "rich", while I would call it "lean" for max power under load, in most cases.

I guess I didn't really answer your question with my ramble! Not sure what the other guys A/F readings were at Thunder, but mine (according to the printout) was down around 9.6 to 1. My gauge shows high 11's to mid 12's right now if I peg it open. 13.5 to 13.9 while cruising at 4 to 4.5K rpm.

 

[Warp12]

I guess I didn't really answer your question with my ramble! Not sure what the other guys A/F readings were at Thunder, but mine (according to the printout) was down around 9.6 to 1. My gauge shows high 11's to mid 12's right now if I peg it open. 13.5 to 13.9 while cruising at 4 to 4.5K rpm.

Yeah, no way that 9.6 is accurate. Dyno sniffers are pretty notorious for issues, and I always trust my data logger more....except in a rare few cases.

 

[tothemax93]

Finally got some miles on the new set up. Went about 150 miles today. I'm very happy with 4000 RPM and up. Pulls fantastic. Below that is OK, for WOT. I could be expecting to much. Rideability between 3 and 4 thousand is good. Checked the mileage today. I got a solid 37 MPG. I'm still not satisfied with the A/F adjustment, But it can't be to far off. The carbs are all over the place with the amount of turns out. For now I have :Morley air box
152.5 mains (stock)
stage 7 needles at 4th clip
Stock PAJ
Floats 17MM
Marks 4-1
A/F anywhere from 1 3/4 to 4 1/2 turns out.

Next step is either getting a wide band or head to the local dyno. Dyno guy gets $115 a session. only a few trips there and I've paid for the wide band. I will hopefully get to the track, but Its supposed to be in the 90's for a most of this week. To hot for this northern boy:bang head:

Turned 40,000 miles on my ride today. I did a ruff estimate since I got the bike. I have about 10 miles of 1/8 (mostly) or 1/4 at a time.

 

[one2dmax]

I do have a wideband unit but you'd need a bung to put the sensor in. It's an LM-2 if I remember correctly.

 

[customizedcreationz]

I am always interested to see on alot of stock bikes how many people have all kinds of aftermarket equipment and run worse than a stock bike or the same as a stock bike. I know lots of aftermarket items are cosmetic bolt ups , ie the velocity stacks people put on the sides of the carbs. They obviously do absolutely nothing other than increase wow factor.

I have nothing done to my bike except a Marks 4-2 exhaust and at the moment have run a best of 11.04@123 ish mph. All stock, no aftermarket jetting, no special intake air filters, no ignition systems, just all factory Yamaha. In fact I am almost willing to bet I could run that number with the stock exhaust, or damn close to it.

I am kinda with some guys on this, if it runs good why mess with it. Once you open it up, you spend tons of time to get it dialed in and even if you dyno it, ask Vmax Mike, his was messed with and messed with and finally after something like 30 continous dyno pulls he pulled a hp number he wanted and thought the bike finally ran strong.

My plugs are white-ish at the end of a run. So yes I am lean. But really fattening it up vs the work and time involved really wasn't worth it for me. Could that have been my magic 10 second number? Most likely it may have been. But I just couldnt pull myself to do it. For the reliability of having a bike that wouldn't be tempermental to weather and other changes. I am running a compromise because its a street bike to me, not a track bike.

I think the Vmax is one of those rare instances that a factory tune is pretty darn good for 90% of everyone out there. And messing with it will sometimes make it worse off than leaving a good thing as it is.

I can vouch for having a bike that makes good street power ( my turbo bike ) but gives me issues now that make it no fun to ride sometimes. So much so that I really really contemplate selling it and buying a stock brand new Busa to ride.

The biggest question you have to ask yourself is, if I am looking to pick up a couple tenths at the track, what reliability on the street am I willing to give up to get it?

 

[m-cman]

I wonder if you have a completely stock Max at sea level, is there any carb adjustments/jetting or other mod that would increase your power? No exhaust changes, just fuel and air intake mods. :confused2: Any one ever experiment with this?

 

[one2dmax]

You can supertune the bike and always get a mild gain. Everything from finding the ideal fuel, to indexing the spark plugs.

Sean

 

[Fire-medic]

Remember this is a bike designed in the early 1980's and as-such, the traditional path to increased horsepower is intake (carbs, filters) and exhaust (new pipe, complete). This is pretty-much true for any UJM of whatever ilk-cruiser, muscle bike, standard, of that era.

To get really increased power from those era bikes, you have to tear it apart and go bigger bore and or stroke, increased compression, bigger valves, high-lift cams, high-performance carburation and then there-goes your ridability, reliability, and wallet-contents. Take a look at Sean's spreadsheets for the costs involved. Please note that due to much experience, people like Sean Morley have developed packages which can retain those elusive qualities a poor hop-up costs you, as in drivability, reliability, and being content w/what you have done.

'customizedcreationz' has a good point about leaving the thing essentially stock. Better tires, brakes, and oil/air filtration, along w/premium oil can make your bike handle better, stop better, and reduce wear on reciprocating parts, while possibly providing you with a smidge more power due to reduced friction and better breathing.

From there, you are limited by only your bank account and the skills of who does the work. Leave it stock, ride it, enjoy it, and watch the other guys spend money like it doesn't matter. In the end, you'll probably be able to ride when they can't because something-else on their bikes need work, or when you go riding, they can't survive in stop & go traffic. Sure it's fun to have a hot bike, but it's no-fun to have a too-hot bike!

Maybe the best answer is to build one bike and keep one stock, and when the Hot Ride gives you mechanical problems, hop onto Mr. Stocker, and experience the most trouble-free riding-from a stock bike. :biglaugh:

 

[Rusty McNeil]

I wonder if you have a completely stock Max at sea level, is there any carb adjustments/jetting or other mod that would increase your power? No exhaust changes, just fuel and air intake mods. :confused2: Any one ever experiment with this?

Smaller mains. 147.5's

 

[tothemax93]

I am always interested to see on alot of stock bikes how many people have all kinds of aftermarket equipment and run worse than a stock bike or the same as a stock bike. I know lots of aftermarket items are cosmetic bolt ups , ie the velocity stacks people put on the sides of the carbs. They obviously do absolutely nothing other than increase wow factor.

I have nothing done to my bike except a Marks 4-2 exhaust and at the moment have run a best of 11.04@123 ish mph. All stock, no aftermarket jetting, no special intake air filters, no ignition systems, just all factory Yamaha. In fact I am almost willing to bet I could run that number with the stock exhaust, or damn close to it.

I am kinda with some guys on this, if it runs good why mess with it. Once you open it up, you spend tons of time to get it dialed in and even if you dyno it, ask Vmax Mike, his was messed with and messed with and finally after something like 30 continous dyno pulls he pulled a hp number he wanted and thought the bike finally ran strong.

My plugs are white-ish at the end of a run. So yes I am lean. But really fattening it up vs the work and time involved really wasn't worth it for me. Could that have been my magic 10 second number? Most likely it may have been. But I just couldnt pull myself to do it. For the reliability of having a bike that wouldn't be tempermental to weather and other changes. I am running a compromise because its a street bike to me, not a track bike.

I think the Vmax is one of those rare instances that a factory tune is pretty darn good for 90% of everyone out there. And messing with it will sometimes make it worse off than leaving a good thing as it is.

I can vouch for having a bike that makes good street power ( my turbo bike ) but gives me issues now that make it no fun to ride sometimes. So much so that I really really contemplate selling it and buying a stock brand new Busa to ride.

The biggest question you have to ask yourself is, if I am looking to pick up a couple tenths at the track, what reliability on the street am I willing to give up to get it?

Have you dyno'ed yours. I would say yours, as a stock bike is considerably above average.Your aggressive launches, and shifts will give a quicker ET but to get that Mph with no work done is impressive. for me Its a labor of love ,so far:eusa_dance: I pulled out my time slip from last year. best quarter was 11.24, 1.78 60 ft, at 119 MPH. just like you, stock except marks 4-1. I think thats respectable, but What the muscle kit has done, is give me a good education. I'm no longer carbfobic, and the changes aren't really that hard. My rideability has proven fine as is, and at this point I have no additonal cost, over the kit. I will dyno at some point, but as long as I'm not obsessive about it, the cost will be minimal. And when all is said and done maybe a few tenths.unk:

 

[tothemax93]

Minor update. I had one of my plugs that no matter where I turned my A/F, It showed lean. Last adjustment was 4 1/2 turns out. The diaphram on that carb was a little suspect. There were no visible holes or tears, but it had cracks around the thick edge, and visibly worn. I got a slide/diaphram from sean and put it in today. I took it for a few mile ride and shut it down at 3000 RPM. pulled the plug and it showed rich (black) as it could be. So my old diaphram was bad, causing a lean condition. I turned the A/F in 1 turn to start. Thats all I had time for today.

 

[Fire-medic]

Minor update. I had one of my plugs that no matter where I turned my A/F, It showed lean. Last adjustment was 4 1/2 turns out. The diaphram on that carb was a little suspect. There were no visible holes or tears, but it had cracks around the thick edge, and visibly worn. I got a slide/diaphram from sean and put it in today. I took it for a few mile ride and shut it down at 3000 RPM. pulled the plug and it showed rich (black) as it could be. So my old diaphram was bad, causing a lean condition. I turned the A/F in 1 turn to start. Thats all I had time for today.

That must have made the stop signs and lights "exciting!":rofl_200:

Glad you were able to get to that point where it seems to be just an adjustment from being fixed.