Seafoam & MPG

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bobbfrommn

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Hi guys. I just purchased an '85 max. Some background; It had been in storage the last two years or so. The guy I bought it from handn't done the mods himself but he thought it had a Stage 3 kit and it looks like Cobra slipons and K&N filters.

He had the bike gone through by a shop and they said they tuned the carbs. Note it was a shop and not a dealer. So here is the deal. There was bad gas in the system and I've been running seafoam through which has eliminated the pops, studders and hesitations. I'm on about tank 3 with the seafoam added each time and my gas mileage is right around 21mpg. Now I'm having fun but I'm not exactly killing it when I ride as I am still getting used to the bike.

So my question is is there a chance that the seafoam is repsonsible for the poor mileage? I've talked to the guy I bought it from and he said it used to run consistantly in the 38-40 range. Or do you think the "carb tune" wasn't really done right?

Outside of this is seems to run fine although it doesn't have quite as much bite as my friend's when you twist the throttle.

Any thoughts would be helpful.
 
Congrats on getting the original. Now the bad news. As a 22 year old vehicle with what doesn't sound like the best recorded maintenance record, be prepared to go through that thing with a fine tooth comb. I'd start with a full rebuild of the carbs . Take your time, and carefully go through things as you discover them. It may be a pain at times, but you'll have the satisfaction of a good machine that you know you can rely on.

Take care...
 
Hi guys. I just purchased an '85 max. Some background; It had been in storage the last two years or so. The guy I bought it from handn't done the mods himself but he thought it had a Stage 3 kit and it looks like Cobra slipons and K&N filters.

He had the bike gone through by a shop and they said they tuned the carbs. Note it was a shop and not a dealer. So here is the deal. There was bad gas in the system and I've been running seafoam through which has eliminated the pops, studders and hesitations. I'm on about tank 3 with the seafoam added each time and my gas mileage is right around 21mpg. Now I'm having fun but I'm not exactly killing it when I ride as I am still getting used to the bike.

So my question is is there a chance that the seafoam is repsonsible for the poor mileage? I've talked to the guy I bought it from and he said it used to run consistantly in the 38-40 range. Or do you think the "carb tune" wasn't really done right?

Outside of this is seems to run fine although it doesn't have quite as much bite as my friend's when you twist the throttle.

Any thoughts would be helpful.


How much seafoam are you putting in each tank? I do not think it would cut your mileage in half.I'd give it some more time on the street.It could get better after you hammer it down some.These carbs need to be cleaned out from time to time.And I mean go out and get some with it.Not disasemble them.These carbs with also gum up easy being putted around taking 2 miles to get to the speed limit.Not that you ride this way.
Doing the peashooter could also help you.It will clean out the choke and pilot air circuts.
 
Bob...

First...congrats on the 85 purchase! Many will argue, but, that is the best of the best.

Get rid of those cobra slips and try to find the 85 canisters if you can (Non DOT approved all USA ;)

I've ran them all, stock - tourmaster (Mark's, HMF, Hindle, UFO)...think I'm liking Mark's and HMF the best.

If anyone jetted the carbs and put the cobra on, they had no idea what they were doing...bet that!

Seriously, have the carbs gone through, tank creamed or replace, and all the fuel system checked out, then replaced.

The flakes that make it past the filter and through the pump are your gas enemy! Abuse all 86 ups you want...please leave the classic alone!

:cheers:

Neil
 
Thanks for the responses so far guys. Now I have permission to go out and hammer it a bit more, think the troopers will accept "but the guys on the forum said I needed to open it up to work through the carbs..."? :biglaugh:

I'll try Shawn's suggestion and give it a few more tanks and see what happens. I'm on my third since picking it up last week. Once I run this one thru I won't add any more seafoam (1oz per gal). Right now it runs fine it just sucks filling up every 70 miles or so. The inside of the tank looked pretty clean and didn't see any crap in there so hopefully that won't be too much of an issue.

As far as the Cobras yeah they are eventually going to go. Either back to stock or UFOs, I'm a sucker for the slash cut look tho. That's probably a next year thing.

-Bob
 
Thanks for the responses so far guys. Now I have permission to go out and hammer it a bit more, think the troopers will accept "but the guys on the forum said I needed to open it up to work through the carbs..."? :biglaugh:

I'll try Shawn's suggestion and give it a few more tanks and see what happens. I'm on my third since picking it up last week. Once I run this one thru I won't add any more seafoam (1oz per gal). Right now it runs fine it just sucks filling up every 70 miles or so. The inside of the tank looked pretty clean and didn't see any crap in there so hopefully that won't be too much of an issue.

As far as the Cobras yeah they are eventually going to go. Either back to stock or UFOs, I'm a sucker for the slash cut look tho. That's probably a next year thing.

-Bob

Buy the HMF's then. I wouldn't give UFO any money... If you have any problems you are on your own buying from him...:bang head: Please take that advice and run with it...:whistlin:

I would replace the fuel filter when you are done with the seafoam. It probably loosend up a bunch of stuff in the tank...:thumbs up:
 
Thanks good suggestion on the filter, I'll order one today maybe can get it done this weekend.

Anyone know where I can find info on the peashooter Shawn recommended? I did a search and found multiple references of people saying to do it but couldn't find any info on what you actually do.
 
The link is in VMF Links. I think it's under Precision Shims or something.

Mark
#1098
 
Thanks for the responses so far guys. Now I have permission to go out and hammer it a bit more, think the troopers will accept "but the guys on the forum said I needed to open it up to work through the carbs..."? :biglaugh:

I'll try Shawn's suggestion and give it a few more tanks and see what happens. I'm on my third since picking it up last week. Once I run this one thru I won't add any more seafoam (1oz per gal). Right now it runs fine it just sucks filling up every 70 miles or so. The inside of the tank looked pretty clean and didn't see any crap in there so hopefully that won't be too much of an issue.

As far as the Cobras yeah they are eventually going to go. Either back to stock or UFOs, I'm a sucker for the slash cut look tho. That's probably a next year thing.

-Bob

depending on how hard I am on the throttle (which I am ALWAYS on it) I fill approx. every 80 miles....mines an 85 also.
 
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