Opinions wanted

[bobbfrommn]

Ok I need your guy's opinion. Few weeks back I bought an '85 max. It came with the Cobra slip-on's and K&N filters. The guy I bought it from couldn't tell me much because he bought it like that but he also said it had stage 3.

The bike had been sitting for a couple of years so there were some residual issues from that. Running seafoam, lubricating a bunch of stuff, changing oil, coolant etc. My next step is going through the carbs & changing the fuel filter on the next rainy day.
My issue is it still doesn't have the punch that I think it should. hmm how to explain it..My friend has an '86 and even before he changed his exaust, a quick twist would bring it up on one wheel or give you that blood flowing to the back of your brain feel. Mine doesn't have that sort of take off, it builds up to speed (quickly) but not just bang-go. Also 22mpg but that is a side issue.

So here is my question. Do you think it's most likely the lack of take off is from the cobra's, poor jetting or not going through the carbs yet? I have a lot of options here and am just trying to figure out the most logical sequence to attack it. My friend has a set of stock pipes from when he changed his so we could try those.

Either way the carbs are going to be done but I'm wondering if I should waste time trying to jet for the cobra's if I am not going to get the result I am looking for. I'm not a big sound guy but I do like the slash cut look of the cobra's and wouldn't mind keeping it. I'd be ok with stock too if a meant a return of the bang-go affect.

If you are reading this and have the cobra's what is your experience? Are you getting the bang acceleration or is it more of a gradual build up? What jetting do you have?
You'll have to pardon me if these are some basic questions or if you have to talk slow. I've never been much for wrenching on things but thanks to my max and a good friend who is a master mechanic I've learned more in the last three weeks than in the last 3 years

Bob

 

[shawn kloker]

I would go through the carbs first.Diaphrams,sync,clogged jets,leaking airbox,carb and vboost boots.Make sure its running on all 4 cylinders.Check the vboost ,is it opening and closing.Check the slack in the vboost cable.Is it opening all the way?

It should still run half decent even with the cobras.They are not that bad.They also can be opened up to breath a little better.

 

[shawn kloker]

I would go through the carbs first.Diaphrams,sync,clogged jets,leaking airbox,carb and vboost boots.Make sure its running on all 4 cylinders.Check the vboost ,is it opening and closing.Check the slack in the vboost cable.Is it opening all the way?

It should still run half decent even with the cobras.They are not that bad.They also can be opened up to breath a little better.

If they are way out of sync it will run like shit!Lose a lot of power too!

 

[maleko89]

How do the plugs look? Spark plug wires?

Mark
#1098

 

[bobbfrommn]

I put new plugs in when I got it and the wires were good. I was going to pull the plugs and take a look now that I've run it for about 300 or 400 miles but it stopped raining this weekend. I'm guessing by the exhaust and one of those test tips that are posted I'm running a bit rich. The v-boost looks to be the same as my buddy's opens just as wide etc, it's nice to have a bike I can put side by side and look at things.

Performance seems ok otherwise, smooth accel, a little hesitation at about 85mph, pulls good to 135 then I usually run out of road . Hard to benchmark against my riding group with the execption of my friend with the vmax they are all on Harleys.

Sounds like it will be best to start with the carbs and go from there. Guess I'll have a day or two of down time, good thing I decided to keep the Maxim X, not quite a vmax but still out runs the rest of the group

Thanks for the suggestions!

 

[one2dmax]

Shawn, I've had the cobra's on my personal bike years ago and the difference was like going from an old 650 maxim to a hell on wheels bike when I got them off of the bike and right to a kerker. I know the stock system will out perform them ANY day of the week. I had even drilled mine out trying to get them to flow better but the real problem is exhaust scavanging. The cobras do not have any scavanging since they don't tie into one another. You may not fully appreciate how much that helps power.

Either way the carbs need a good cleaning and sync.

Sean Morley

 

[shawn kloker]

Shawn, I've had the cobra's on my personal bike years ago and the difference was like going from an old 650 maxim to a hell on wheels bike when I got them off of the bike and right to a kerker. I know the stock system will out perform them ANY day of the week. I had even drilled mine out trying to get them to flow better but the real problem is exhaust scavanging. The cobras do not have any scavanging since they don't tie into one another. You may not fully appreciate how much that helps power.

Either way the carbs need a good cleaning and sync.

Sean Morley

Sean,Wouldn't his stock headers still have the 1-4 crossover in there under the motor?

My Hmf's are 1&4 in one header and 2&3 in the other.

 

[one2dmax]

Yea, but without the rear junction to hook the others together it's like pissing in the wind.

Sean

 

[bobbfrommn]

Gonna start the carb work tonight I think. After all this discussion I may go back to the stock and loose the slip-ons. At least till I decide which way I want to go on a full system.