After NUMEROUS attempts at getting this thing running right to no avail..... IM DONE! :bang head: I've had the carbs off and gone through 3 TIMES and it'll run good for a bit and then back to the same old bulls**t! The first time I had the carbs crone through it ran good for 800 or so miles before it started running like a single cylinder Pyle and the last two times they were off it only ran good for 2-4 miles, yes that's right, not 24, 2-4 :bang head: This last time I took the gas tank off and cleaned it out, took the fuel pump apart and checked it, replaced the fuel filter, cleaned pretty much everything gas touches. I don't know where else to go with this thing! If it was an air leak I would think it would run good at all once the carbs were put back on, not even for a few miles. I don't want to keep dumping money into a bike that's only worth a few thousand dollars
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one2dmax
Well-Known Member
Do you need to borrow an electrical test kit to make sure it's not electrical related?
What are you thinking the culprit could be electrical wise? I have COP's on it now but that's all I've changed. I have a multimeter but not a lot of electrical experience so I would have to do some reading on here. The bike had 170 mains in it when I got it and I went to 150's and it pops a lot on deceleration which obviously points to it being lean but it does it with the 170's also. So one would think an air leak right? Wouldn't an air leak make it run like shit all the time though? The fact that it ran good for a few miles made me think it was fuel/carb related.
davesax36
Well-Known Member
Mikuni 170 and dj 170 are really different. Where'd you get your cops? Decel pop from the exhaust is, I believe, from the coasting enricheners and unburned fuel going out the exhaust valves or a loose exhaust connection, not an intake air leak. Lean condition would give you hanging revs on throttle blips and coughing back up through the carbs. Really bad sync can cause some terrible response, too.
I got the COPS from blaxmax on here. I have a carbtune and the sync is good. I don't remember if they are DJ or mikuni, I actually have the 150's in now. I had a two brothers full 4-1 exhaust and took the can off and put a single universal open end supertrapp on. I also have a drop in k&n.
one2dmax
Well-Known Member
Did you remove the intake at all? The left front and right rear are shorter bolts. If the wrong length is used it will not snug up properly and an air leak can occur. Try going back to a stock coil setup for now just in case you have a bad COP coil (it happens).
CDI Box and Pickup Coils can go bad and make weird shit like this. Even sidestand relay and main diode packs. Carb throttle shafts and more. I have not ever made one but it might be worth looking at or making a leak detection kit using smoke or even carb cleaner but careful using that as it can strip or dull the paint. I've also seen it done using a gas but can't remember if it was propane or some other inert gas?
CDI Box and Pickup Coils can go bad and make weird shit like this. Even sidestand relay and main diode packs. Carb throttle shafts and more. I have not ever made one but it might be worth looking at or making a leak detection kit using smoke or even carb cleaner but careful using that as it can strip or dull the paint. I've also seen it done using a gas but can't remember if it was propane or some other inert gas?
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I didn't take the intake off at all. I don't have the original coils and wires anymore. Is there any way to test the cdi box? If I take it to a shop I'm sure they'll charge me $400-$600 to rebuild the carbs even though they don't need it and once that doesn't fix it I'll have to pay even more for them to figure out what is actually wrong!
davesax36
Well-Known Member
Get the electrical test kit from Sean. It really helps eliminate those things.
davesax36
Well-Known Member
Start with all the stuff and eliminate one component at a time.
Sean, propane from a torch, not lit, should make the bike pick-up rpm's if it gets sucked into a leaky manifold.
Yes, ask to borrow Sean Morley's electrical kit, you only pay for what you need to fix your problem. A great service, from a very knowledgeable person about our bikes.
Yes, ask to borrow Sean Morley's electrical kit, you only pay for what you need to fix your problem. A great service, from a very knowledgeable person about our bikes.
Trying to analyze what the OP stated..
If the bike carbs where rebuilt, and after testing, the bike ran fine, then around 800 miles or so, it started acting up again,, THEN, after another cleaning, it ran fine for a much shorter period of time.. Maybe I'm wrong, but I would think that if its something electrical or air leakage,, it should show itself pretty quickly, or at least till the bike warmed up (like the pick-up coil would do).
The performance boost, only after a cleaning, almost sound like some foreign matter is being knocked loose and clogging things up.
I had a hell up a time trying to get mine from stumbling around 4-5k. No matter how much I tried to clean the tank, that damn ethanol would draw water in from the atmosphere and caused rust to develop in my tank and subsequently anything else in the fuel system.
Finally on the 4th time pulling the tank, I said F_ck this,, I coated it with the KBS tank sealer kit.. While that was drying, I removed the fuel lines, took apart the pump, and broke down and cleaned all the carbs. and lines.
After all that work, I didn't want any foreign matter in my system. So, to remove anything I couldn't get too, I put 1/2 bottle of SeaFoam in a full tank. By my 2nd application of Seafoam, the stumble was gone, and has not come back.. 3 years so far, and running strong..
Chances are, if you open one of your carbs, you'll see rust..
Even after cleaning my carbs in an Ultra-Sonic cleaner, then running the bike for about 50 miles, I would crack open a carb and it looked like I did not clean it at all.
So, I figured I'd attack it at the source,, the fuel tank.
If the bike carbs where rebuilt, and after testing, the bike ran fine, then around 800 miles or so, it started acting up again,, THEN, after another cleaning, it ran fine for a much shorter period of time.. Maybe I'm wrong, but I would think that if its something electrical or air leakage,, it should show itself pretty quickly, or at least till the bike warmed up (like the pick-up coil would do).
The performance boost, only after a cleaning, almost sound like some foreign matter is being knocked loose and clogging things up.
I had a hell up a time trying to get mine from stumbling around 4-5k. No matter how much I tried to clean the tank, that damn ethanol would draw water in from the atmosphere and caused rust to develop in my tank and subsequently anything else in the fuel system.
Finally on the 4th time pulling the tank, I said F_ck this,, I coated it with the KBS tank sealer kit.. While that was drying, I removed the fuel lines, took apart the pump, and broke down and cleaned all the carbs. and lines.
After all that work, I didn't want any foreign matter in my system. So, to remove anything I couldn't get too, I put 1/2 bottle of SeaFoam in a full tank. By my 2nd application of Seafoam, the stumble was gone, and has not come back.. 3 years so far, and running strong..
Chances are, if you open one of your carbs, you'll see rust..
Even after cleaning my carbs in an Ultra-Sonic cleaner, then running the bike for about 50 miles, I would crack open a carb and it looked like I did not clean it at all.
So, I figured I'd attack it at the source,, the fuel tank.
So the time it ran good for 800 or so miles it actually wasn't the same problem (before the 800) as now. Before it was a hesitation or stumble if I tried to hold a steady freeway speed. After the 800 miles it would pop on deceleration and if I try to cruise at any speed. Also, instead of accelerating like a Vmax it's more like a moped! It feels like its being starved of gas and sometimes If I stay in it hard for a split second it's like I will feel the regular Vmax acceleration and I do mean a split second.
But even right after I put it all back together and it "runs good" for a few miles I still get popping on deceleration and it's still not perfect but it accelerates like it should.
D-Max
When I took the tank out I got just about zero sediment out of it, I didn't coat it though. I also took the fuel lines and fuel pump off and cleaned/disassembled. I also put hose clamps on the filter and pump lines just to make sure no air was getting in there. Maybe I should try to post a video but chances are you wouldn't be able to tell on a video. Is posting a video on here the same as posting a picture?
D-Max
When I took the tank out I got just about zero sediment out of it, I didn't coat it though. I also took the fuel lines and fuel pump off and cleaned/disassembled. I also put hose clamps on the filter and pump lines just to make sure no air was getting in there. Maybe I should try to post a video but chances are you wouldn't be able to tell on a video. Is posting a video on here the same as posting a picture?
davesax36
Well-Known Member
How's the sync? Wet float levels? Are you fouling plugs?
Dry float levels were right at that little circle mark in the float bowl. Last time the sync was just about perfect. This last time 3 were even and one (front right cylinder) was even but it was bouncing. I replaced the plugs last time but not this time and I haven't checked them yet.
sdt354
Well-Known Member
jdeitz1979
Well-Known Member
Just out of curiosity, have you checked your connectors for the cops. You know, the plug and play ones?? I went thru this kind of thing with mine right after installing the cops. The plug and play connector could have a loose wire or a bad connection. I found the crimps on mine were not so tight causing me to chase them. It's worth a look. Maybe I've already suggested this.. idk. But I would definitely take a look in that direction. Especially if your problem did not exist prior to cops
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Thanks for all the replies.....
I contacted Sean and he is going to send me the kit. I haven't done a set float check ever but I know there is a sticky on how to do it so I'll check that out. I've thought about just getting a new fuel pump from eBay for $20 or $30 but This thing is nickel and diming me to death! Not to mention when and if I get this stuff figured out I need to replace the fork seals (one is leaking bad), water pump seals, new front brake rotors because these are warped... it's never ending
I contacted Sean and he is going to send me the kit. I haven't done a set float check ever but I know there is a sticky on how to do it so I'll check that out. I've thought about just getting a new fuel pump from eBay for $20 or $30 but This thing is nickel and diming me to death! Not to mention when and if I get this stuff figured out I need to replace the fork seals (one is leaking bad), water pump seals, new front brake rotors because these are warped... it's never ending
