Please help. My Max runs like garbage.

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Wolfemax

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Hey,
> I've got an '85 Max with a stock airbox, K&N filter, Supertrapp slip-ons, and a Dynojet Stage 1 kit.
> My problems started (I believe) as a result of putting too much carb cleaner in my gas tank (not intentional - long story). After that it started running terrible, but after a bit, I got it cleaned up and it ran well again. For the rest of that summer, it would occasionally run like crap, but if I got the revs past 5k, it would clear up, and then be fine for a few weeks. One day I went to start it, it fired up, ran like crap for about 30 seconds, died, and refused to restart. I drained the carbs and they were full of rust. I removed the gas tank, had it cleaned and lined, and put in a new fuel filter. I got carb kits for my bike, and started cleaning the carbs. One of the carbs' pilot screw was so seized that there was no way to get it out without damaging the threads. I bought a replacement carb body on ebay, but it's threads were screwed up too. Along with my ebay purchase, I got four 34mm carb bodies from a Venture. I put the carb kits in the 34's and put them on my Max. It ran well 'til about 4k, but that was it. I got another 35mm carb body from ebay, swapped the stuff over, and tried running my 3 original 35's plus one "new" one. It ran ok from idle to 4.5k, ran like crap til about 6k, and then ran ok after that. I put in the 170 main jet from the DJ kit, and set the needles as high and they would go which improved the performance, but I still got better response with the choke on, and power improved once the bike warmed up. Over the course of that summer, I must have had the carbs off a dozen times, cleaning and trying to solve the problem. I took the carbs apart again over the winter, and had the bodies and the jet blocks cleaned in a sonic tank. I put them together again and it ran like crap. I swapped jet blocks and things improved - but still nowhere near the power I should have. I tried going down a couple of settings on the needles, and went down to the DJ 165 main jet. Now, the bike falls on it's face at 4k, but if I hold it wide open (and use some choke) I can get it past 6k and then it will take off. I can go through the gears and as long as I stay above 7k or so I've got lots of power - almost as much as I should. If I'm just cruising, the power falls off as soon as I use more than 1/8th throttle. If I want to hold highway speeds in 5th gear I have to hold the throttle wide open. I pulled the plugs the other day and they were white. I took the lid of my air box tonight, and when I held the bike at 3-4k, the slides fluttered like mad.
> The Dynojet kit was first installed with the 34mm carbs.
> Any ideas?
> Thanks for listening.
> Jason.
 
Jason: Ask if anyone on list is close to you. Might be able to help you. Check fuel pump, ck vacuum, sync carbs(just helps down low), a vacuum ck would also help find leaks, old rubber, If all plugs look good, I dought it would be coils, wires, plugs, etc.... good luck. sandy ps. go back to std jetting, and carb settings, once you resolve problem. play with others.
 
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Get rid of the stage 1 kit COMPLETELY and reinstall all the stock parts and a Mikuni 147.5 main and then see where you are.

That DJ kit isn't at all needed for just slip-ons and usually causes more issues than anything.

I see you've had them apart NUMEROUS times. How many times have you sync'd them?

Chris
 
Sandy - I replaced the fuel pump a couple of days ago (I had one from a parts bike) - no change, I've sync'd the carbs almost every time after putting them back on - including the last time, I haven't checked the vacuum yet - any tips on the best way to do that?

4gasem - I've drilled the slides, and I don't have any spares - should I fill the holes with epoxy and re-drill them to the correct size as well as swapping out the DJ parts?

Buster - I'm in Winnipeg.
Thanks for the responses.
Jason.
 
I wouldn't worry about the slides, they are the least of your problems. As Chris said, go back to stock needles and Mikuni 147.5 main jets. Re-synch and go from there. That DJ kit is JUNK of the highest magnitude, I tried like mad to get one to work a couple of years ago and went through 2 weeks of BS before I gave up and tuned the bike the right way. Now if you go with an aftermarket exhaust, full system, then my first call were I in your shoes would be to Sean Morley and get one of his jet kits......
 
I believe the stock jets I have are 152.5's. Should I be getting some 147.5? Where from?
Thanks,
Jason.
 
When you put on slip ons the bike will go rich. Go to your local dealer, would send you to Sean Morley but shipping would cost more than the jets, and tell them you want the small diameter Mikuni 147.5 main jets. Take your 152.5's with to compare the outer diameter to make sure that they have the right ones. Go from there.
 
I'm sure you probably have done it but just in case have you set the float levels?
Check for vacuum by spraying carb cleaner arround the intake rubbers, including arround the vboost manifolds.
What altitude is it where you live? How are the diaphrams on your slides? I would also put the stock slide springs back in. Do you get any change in idle when you adjust the mixture screws?
I would also go to a set of COP's. I had more than 1 problem and thought it was all carb. It is cheap to buy them off ebay and was easy to do the change.

Good luck
Jim
 
Not to steal this thread, but, i have supertrapp s.o's, K&N, T-boost- 3000 rpm, & stage one kit. Seems to run good, synch's out fine, pulls good all gears. I do get a tiny bit of black smoke if only cruising for a while then getting on it. Do you think i would be further ahead to go with your jetting sizes, also??? One thing seems odd, I ran it at the drag strip, ran 11.6, but only best of 113 mph. Seems like it should be higher???
 
tvmax
I have set the float levels, but I'm not above checking them again.
The altitude here is about 770 feet.
The diaphrams look good.
"I would also go to a set of COP's. I had more than 1 problem and thought it was all carb. It is cheap to buy them off ebay and was easy to do the change." Pardon my ignorance but what are COP's?
Thanks,
Jason.
 
tvmax
I have set the float levels, but I'm not above checking them again.
The altitude here is about 770 feet.
The diaphrams look good.
"I would also go to a set of COP's. I had more than 1 problem and thought it was all carb. It is cheap to buy them off ebay and was easy to do the change." Pardon my ignorance but what are COP's?
Thanks,
Jason.

The COPs are Coil Over Plug, which is a replacement for the stand alone coil set up. But you should really put your carbs back to a stock set up as suggested earlier in this thread. Get that squared away first before looking at the other suggestions.
 
Trust the people that know! GO BACK TO STOCK! Last year a guy with a VERY similar setup ran 116bhp with a 152.5 jet and he was rich so Sean sold him 4 147.5 jets to install.

Chris
 
Jason,
I also suggest going to stock first on the carbs. I also suggest the cops because it is a cheap replacement/upgrade from stock coils. I had more than 1 problem. If you get your carbs to stock and still have trouble I wold look at a set. My carbs had problems but the coils did also.

Good luck
 
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Hey 4gasm, were you refering to my post of my setup when you said go back to stock.
thinking of going with Morleys setup anyway. till then, you think the stock needles, jets, & slide springs are better than the dynojet stuff. What about the hole in the slides. I think I have some 150 mikuni jets laying around, 7 the stock 152.5's
 
Just a word to bring closure. I was cleaning my carbs last week (for the 15th time) when I looked closely at the needle jet that was included in the carb kits I got when I first started having trouble. The hole that allows the fuel to flow from the main bleed pipe in the jet block was drilled in the wrong place (90 degrees off). The carb kits were made by Keyster. I replaced the needle jets with the ones that were in my carbs originally and the thing runs awesome.
Thanks to all who responded.
Jason.
 
Screw the Keyster kits. We had a bike come in with those kits and they had tried everything including getting another carb body set from me. Once I found out they had put the Keyster kits in I had them bring the bike back in and put oem stuff in. Ran perfect after that. The bike would only idle with the kits in place.

Sean
 
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