MM EFI Rears it's ugly head
#1
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[rant]
The thing is driving me nuts!
Couple months ago when it warmed up, went for a ride. Spat, spuddered, and backfired for a bit, got warm, went away. Was very humid that day, so figured it was the plug wires. Changed those, didn't get much time to test ride since the weather turned to chit, but "seemed" ok.
Day after Christmas, went for a ride. Thing wouldn't idle below 3,000 r's. Rode it straight to the dealership, turned out it was the Idle Speed Motor. Changed under extened warranty, and ran good.
Yesterday, hits 66* here. Got the bike out at lunch, no problems getting to the shop. Take off for a Dr's appt and the Rice Crispie Syndrome hits again. Twas emberrasing riding thru town. Thing sounded like a machine gun going off. By the time I got to the dealer, it had cured itself again. No service techs on duty yesterday (WTF?) so I just just rode it back home the long way. 66* here in January is rare
Salesman (used to be a tech) said most likely the head temp sensor or the intake gasket. He really didn't have anything good to say about the MM ignition
All I know is the last two rides, two problems. Hope things settle out with it. Would hate to be nervous about taking a long trip. Tis the reason I got it. Bought it used in October, and this is the third time it has been to the shop. Only put 1,200 miles on it in that time, so not a very good "riding to wrenching" ratio
[/rant]
The thing is driving me nuts!
Couple months ago when it warmed up, went for a ride. Spat, spuddered, and backfired for a bit, got warm, went away. Was very humid that day, so figured it was the plug wires. Changed those, didn't get much time to test ride since the weather turned to chit, but "seemed" ok.
Day after Christmas, went for a ride. Thing wouldn't idle below 3,000 r's. Rode it straight to the dealership, turned out it was the Idle Speed Motor. Changed under extened warranty, and ran good.
Yesterday, hits 66* here. Got the bike out at lunch, no problems getting to the shop. Take off for a Dr's appt and the Rice Crispie Syndrome hits again. Twas emberrasing riding thru town. Thing sounded like a machine gun going off. By the time I got to the dealer, it had cured itself again. No service techs on duty yesterday (WTF?) so I just just rode it back home the long way. 66* here in January is rare
Salesman (used to be a tech) said most likely the head temp sensor or the intake gasket. He really didn't have anything good to say about the MM ignition
All I know is the last two rides, two problems. Hope things settle out with it. Would hate to be nervous about taking a long trip. Tis the reason I got it. Bought it used in October, and this is the third time it has been to the shop. Only put 1,200 miles on it in that time, so not a very good "riding to wrenching" ratio
[/rant]
#2
#3
#4
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ORIGINAL: Firetender
Pete, hope you can get a handle on your issue, or maybe a better diagnostician. Is there another shop in your area? These things are usually due to a $5 part that you replace as a $ 75.00 item!
Pete, hope you can get a handle on your issue, or maybe a better diagnostician. Is there another shop in your area? These things are usually due to a $5 part that you replace as a $ 75.00 item!
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Just concerns me what I have read (hind sight) and I got this to put some longer distance trips than I have been able to before.
Will find out for sure in May, just 800 miles from here to MBBW
#5
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There are those that the MM works just fine, and then others that it just gives fits every time ridden. I dont have a lot of experience with that system, but I do know a couple of guys I ride with that have converted to carbs to get away from the problem. There is also a conversion to the Delphi system but it is pretty pricey from what I have read.
#6
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Dalton is right. My old MM bike ran great, even with a mild 95" kit on it. Other bikes I've known have never ran right from the begining. No logic to it. Eliminate the easy stuff like intake/exhaust leaks, worn parts etc. You might consider have buying a race tuner and having it tuned by a good shop if you have one local to you. Would probably cost about the same to convert it to a carb also. You have options.
Nice looking bike, don't give up to easy.
Nice looking bike, don't give up to easy.
#7
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ORIGINAL: Biggzed
Dalton is right. My old MM bike ran great, even with a mild 95" kit on it. Other bikes I've known have never ran right from the begining. No logic to it. Eliminate the easy stuff like intake/exhaust leaks, worn parts etc. You might consider have buying a race tuner and having it tuned by a good shop if you have one local to you. Would probably cost about the same to convert it to a carb also. You have options.
Nice looking bike, don't give up to easy.
Dalton is right. My old MM bike ran great, even with a mild 95" kit on it. Other bikes I've known have never ran right from the begining. No logic to it. Eliminate the easy stuff like intake/exhaust leaks, worn parts etc. You might consider have buying a race tuner and having it tuned by a good shop if you have one local to you. Would probably cost about the same to convert it to a carb also. You have options.
Nice looking bike, don't give up to easy.
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#8
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I can see why the guy is a salesman instead of a tech. Neither the head temp sensor or the intake gasket (really a seal) are very good guesses. I'm not saying everyone has had the same experience, but I've found the MM system to be as reliable as anything else and easy to work on. First, if you don't have one, get a service manual. The diagnostics in it are very good. As far as your current problem goes. remove the air cleaner and take a look at the throttle plates. Each one is screwed to a shaft that rotates when you apply the throttle. Older ones tend to fracture, and the plates then sometimes stick and sometimes work well. When they stick, the bike runs like crap.
#9
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Alot of times erratic conditions in the MM fuel injection can be cured with a hot/cold idle adjust. I would mention it if you take your bike in and be sure to mention service bulletin M-1105!!! The old way of correcting this problem was iffy at best and took approximately 4 hours according to book.
#10
Join Date: Feb 2005
Location: San Antonio Texas
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Have them run a pressure test on your Fuel Pump. Sounds like you have a leak in the fuel line inside the tank. I had the same problem a couple of summers ago and if you know what you are looking for it's an easy fix (for a tech). I found the info here on the forum.
Terry
Terry