M38A1
Admin
Well, a few months ago I broke down and purchased a 1996 DR350SE from a fellow forum member. I blasted out to New Mexico, talked a bit more on the 'project bike' and a deal was struck.
From the PO, the bike wasn't being used much, probably needed a good carb cleaning and has a charging issue with either the stator or rectifier not working properly. Good tires, not really abused, 14K miles, larger fuel tank, bark busters and some Wolfman soft luggage, SAE pigtail and BatteryTender as part of the package.
I got it home and shortly thereafter emptied the fuel tank/put in fresh fuel and tried to get it to start. No joy. Not even really a 'pop' so to speak. So I poked around a bit on the web and saw valve adjustments kept popping up as a possible hard start culprit. So I dove in and adjusted the valves. Still no joy in starting.
Wondering if there were some more serious problems, I checked I had good spark and I did. I checked I had compression and that seemed good with my finger over the hole and trying to get my compression tester to work properly. And I checked that I had a good fuel supply from the tank which I did. It should at minimum fire, right?
So I tried a bit of starting fluid, and presto - it popped and sputtered! That confirmed I had a reasonably good top end for compression/spark so that just left fuel as the next thing to attack.
https://youtu.be/xLQJKnqiOYk
The little bike just sat in the garage for a while looking all sad, so Rusty offered up his experience in carb cleaning. Yesterday I pulled the carb out (an aftermarket Mukuni pumper TM33-8012) and we did a deep clean on most of it. There was one cover we didn't take off, yet apparently it was the slide access so not really necessary? Anyways, with a clean carb I got home and installed it, put the fuel tank on with a gallon of fresh fuel and hit the start button. Within a few seconds it fired up and ran! Not smooth, but it was running..... Choke was on and once it warmed up, pulled that off and it evened out. So I'm thinking I need to adjust the air/fuel screw next.
https://youtu.be/zC7VhuDN_JI
While that was going on, I had a voltmeter hooked up to the battery as the stator/rectifier issue was in the back of my head. Throughout the starting process I noticed the voltage was 12.25v, then as it was running it dropped to 12.23, then 12.21, then 12.19. ie: the battery was draining, not charging around 14 as where I would have expected it to be.
So I shut it down and thought for a minute, how do I troubleshoot these two components as I don't want to just replace the easy rectifier and have it be the stator. Gets kind of spendy at that point.
While pondering that, I remembered the headlight was 'weird' in that the low beam was pointing pretty high and the high beams when turned on went low. Hmmmm.... A quick look at the big rectangle bulb showed me it was upside down! So I swapped that orientation.
Which leaves me to my question for the moment...... Just how do I test the charging system to determine which (or both) is at fault? I have a simple voltmeter and that's about it along with a limited knowledge of how electrical stuff really works.
Any help would be much appreciated!
From the PO, the bike wasn't being used much, probably needed a good carb cleaning and has a charging issue with either the stator or rectifier not working properly. Good tires, not really abused, 14K miles, larger fuel tank, bark busters and some Wolfman soft luggage, SAE pigtail and BatteryTender as part of the package.
I got it home and shortly thereafter emptied the fuel tank/put in fresh fuel and tried to get it to start. No joy. Not even really a 'pop' so to speak. So I poked around a bit on the web and saw valve adjustments kept popping up as a possible hard start culprit. So I dove in and adjusted the valves. Still no joy in starting.
Wondering if there were some more serious problems, I checked I had good spark and I did. I checked I had compression and that seemed good with my finger over the hole and trying to get my compression tester to work properly. And I checked that I had a good fuel supply from the tank which I did. It should at minimum fire, right?
So I tried a bit of starting fluid, and presto - it popped and sputtered! That confirmed I had a reasonably good top end for compression/spark so that just left fuel as the next thing to attack.
https://youtu.be/xLQJKnqiOYk
The little bike just sat in the garage for a while looking all sad, so Rusty offered up his experience in carb cleaning. Yesterday I pulled the carb out (an aftermarket Mukuni pumper TM33-8012) and we did a deep clean on most of it. There was one cover we didn't take off, yet apparently it was the slide access so not really necessary? Anyways, with a clean carb I got home and installed it, put the fuel tank on with a gallon of fresh fuel and hit the start button. Within a few seconds it fired up and ran! Not smooth, but it was running..... Choke was on and once it warmed up, pulled that off and it evened out. So I'm thinking I need to adjust the air/fuel screw next.
https://youtu.be/zC7VhuDN_JI
While that was going on, I had a voltmeter hooked up to the battery as the stator/rectifier issue was in the back of my head. Throughout the starting process I noticed the voltage was 12.25v, then as it was running it dropped to 12.23, then 12.21, then 12.19. ie: the battery was draining, not charging around 14 as where I would have expected it to be.
So I shut it down and thought for a minute, how do I troubleshoot these two components as I don't want to just replace the easy rectifier and have it be the stator. Gets kind of spendy at that point.
While pondering that, I remembered the headlight was 'weird' in that the low beam was pointing pretty high and the high beams when turned on went low. Hmmmm.... A quick look at the big rectangle bulb showed me it was upside down! So I swapped that orientation.
Which leaves me to my question for the moment...... Just how do I test the charging system to determine which (or both) is at fault? I have a simple voltmeter and that's about it along with a limited knowledge of how electrical stuff really works.
Any help would be much appreciated!
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