VMax Journey Continues....

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HDKILA

Well-Known Member
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Sep 24, 2008
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Location
Saint Charles, IL
I am taking my bike over to Jeff's (huberjw) today for him a few other members on the forum to try and figure out what the hell is up with my mad max. He has asked me to make a thread about all the things I have done to try and cure my high rpm miss issue. I wanted to also creat this thread to allow any other members to give there opinion on what they think at this point. Please read through the entire thread before commenting as I have done ALOT of things at this point to cure this problem.


I bought the bike in early october and noticed right away it had a significant miss in the upper rpm. I got her home and inspected the easy things like the airbox and whatnot. The airbox had 8-10 dead mice in it and the baby mice had chewed the air filter up pretty badly.

I then proceeded and checked out the fuel filter. The fuel filter was original (my bike is an 85!) and had a ton of rust and shit in it.

At that point I talked to you guys about it and ended up taking off the fuel tank and getting it cleaned and epoxied. At that time I also replaced the fuel filter and fuel lines.

After that I sent my carbs to mark (maleko) to get cleaned and inspected. He tested my carbs on his bike and his bike ran great after the cleaning and he experienced no high rpm miss.

Once I got the carbs back I put them on and was still getting a high rpm miss. I started going through the electrical at this point.

I replaced my coils, plugs, wires, caps, ignition and rectifier/regulator. Still no dice!

Then when I as synching the bike I noticed hearing what sounded like an air leak. I sprayed around my carb boots with wd40 and my idle shot up. I was sure I finally found my issue and ordered all new carb boots.

I installed the carb boots, synch'd up and still no dice!

During this whole process I disconnected my v-boost fully open just to rule out the v-boost. My bike does seem to have an issues with the v-boost cycling every time the key is turned. Sometimes it does sometimes it doesn't cycle.

Other than that I have replaced the oil/oil filter, tires, brake fluid and pads, installed a new seat, and new brake rotors. These things do not pertain to the rpm miss but I thought I would mention them.

I will be leaving shortly to go to Jeff's and I wanted to again thank him for doing this for me. I also wanted to thank Mark as he has been of great assistance the last few months trying to cure this animal.

Jeff told me that Morley was thinking of coming up and helping one weekend if he and 4gasm can't figure it out. If you do please know that I would be willing to reimburse for gas and any other expense (that goes for 4gasm as well).

At this point I want to just be able to enjoy the bike this summer and not be working on it other than to do routine maintence.

Thanks again to everyone who has helped and of course this website. This forum has served me well beyond my expectations and deserves to be recognized for it!

I will keep everyone posted on the situation via this thread and if anyone has any suggestions for Jeff please post them here.
 
Take a deep breath and relax. With Sean, Chris and Jeff you will have a running bike for the summer :eusa_dance: It couldn't be with better people.
 
Just to throw something out there, you might want to take a look at the ignition pickup sensors. Sounds like you have pretty much checked most everything else.
 
+1 Jim. The vboost not always cycling could be an issue too. Other than that, I would go through the harness especially if mice were in the bike. They chew on everything.

Abe, with these guys working on it you'll have a reliable bike to ride before spring. :)
 
During this whole process I disconnected my v-boost fully open just to rule out the v-boost. My bike does seem to have an issues with the v-boost cycling every time the key is turned. Sometimes it does sometimes it doesn't cycle.


if thats the one thing that is def not working 100% right now, maybe check that out for now? just my $.02..

aside from that you have the bike in great hands!

Also don't forget your new battery!
 
Not 100% sure on my trip up there but I might just have to do that.

Sean
 
Beers and strippers!!!!!!!! Now, I just need to get the strippers and we'll be in business!!!! If anyone else wants to come down, the more the merrier! Also, keep throwing out ideas to help us out. I'll try to document everything I do, but with it being 20 degrees out, putting this bike in real life riding situations is going to be a little tricky.
Thanks,
Jeff
 
yea, pictures and this being well documented i'm sure will be a wealth of knowledge for yrs to come!
 
Just an idea, but could valves adjustment help here?

I also still would like a more detailed description of the 'miss at high rpm". What happens exactly? At what rpm? Every time you hit a specific spot, or within a range? Also, every time or some times? In every gear?
 
Just an idea, but could valves adjustment help here?

I also still would like a more detailed description of the 'miss at high rpm". What happens exactly? At what rpm? Every time you hit a specific spot, or within a range? Also, every time or some times? In every gear?

I was wondering the same thing, or maybe even gummed up valves?
 
The bowl vent tubes would be my first check. Make sure they're there and that they aren't chewed up.

As for reimbursing me for fuel... What ever! I need to catch up with Jeff anyway. Haven't seen him since what??? October?

Let me know Jeff. I think Susan works a lot this weekend so I am open to coming down I think.

Chris
 
I think this weekend will be open for me... somewhat. The wife and I are working on the basement and trying to get it tuckpointed and painted, so I'll be working on that on and off, but I'm sure I can get one of the days off this weekend. I need to get some of the "crap" out of the garage first so I can make a good working area for Abe's bike. If you do come down, I may try to talk you into helping me put my forks/seals back on my 02. I have been putting it off since the drag bike has come to life. I'll either give you a ring or feel free to give me a call if you have some free time on your hands.
Thanks!

Jeff
 
I'm just trying to get as many people over here so I can sit back and drink a few beers!!! I think they call that "supervising" or is it "stupidvising"
 
I think this weekend will be open for me... somewhat. The wife and I are working on the basement and trying to get it tuckpointed and painted, so I'll be working on that on and off, but I'm sure I can get one of the days off this weekend. I need to get some of the "crap" out of the garage first so I can make a good working area for Abe's bike. If you do come down, I may try to talk you into helping me put my forks/seals back on my 02. I have been putting it off since the drag bike has come to life. I'll either give you a ring or feel free to give me a call if you have some free time on your hands.
Thanks!

Jeff

Do you have the seal driver? I do in case you don't... I thought you said you did though.

Let me know. One of those days I have to go out with Susan. Not sure. We can hold off till the next weekend too.

Chris
 
Well, I got a brand new 85 Vmax in my garage now. Abe dropped it off late this morning. I have started to tear into it a little. He complained about the battery being down a little after a week or two of sitting, so I did a quick short check and all the fused wires look good, but I was getting about a 0.25 voltage drop to the R/R. Now this is a new (BUT USED) R/R that I picked up and sold to Abe (I was going to use it on my drag bike) but he was needing it before I would, so I sold it to him for what I had in it. I had since purchased another R/R from a Suzuki to use for my drag bike. I put it on and got about a 0.13 volt drop.

I did a quick check on my 02 (with a stock R/R) and it has a 0.12 voltage drop. Is any of this normal or has anyone else had any issues with a newer style R/R?

I'm wondering if these newer R/R's should be hooked up to a switched positive? Any thoughts?

Thanks,

Jeff
 
Do you have the seal driver? I do in case you don't... I thought you said you did though.

Let me know. One of those days I have to go out with Susan. Not sure. We can hold off till the next weekend too.

Chris

Might as well bring it.

Thanks,
Jeff
 
Well, I got a brand new 85 Vmax in my garage now. Abe dropped it off late this morning. I have started to tear into it a little. He complained about the battery being down a little after a week or two of sitting, so I did a quick short check and all the fused wires look good, but I was getting about a 0.25 voltage drop to the R/R. Now this is a new (BUT USED) R/R that I picked up and sold to Abe (I was going to use it on my drag bike) but he was needing it before I would, so I sold it to him for what I had in it. I had since purchased another R/R from a Suzuki to use for my drag bike. I put it on and got about a 0.13 volt drop.

I did a quick check on my 02 (with a stock R/R) and it has a 0.12 voltage drop. Is any of this normal or has anyone else had any issues with a newer style R/R?

I'm wondering if these newer R/R's should be hooked up to a switched positive? Any thoughts?

Thanks,

Jeff

You could but then wouldn't it be harder to diagnose a problem with the red wire grounding somewhere within the R/R? If you unplug the stator connection does the drop go away? I'll have to check mine to see if there's a drop.
 
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