Voltage regulator/rectifier question

[Jayceesfolly]

I have a 83 VR with an 86 motor (previous owner changed motor, instead of fixing 2nd gear) and have bought a heavy duty stator and regulator/rectifier from Buckeye Perf. and installed the stator OK and works good, but then noticed that the instructions for the R/R said to cut off the brown wire in the wiring harness and discard it. The R/R is a knockoff and not a Yama part. I am wondering what the brown wire is used for and if I can cut it off without any bad effects. Can I safely cut and discard this brown wire? Electrical wiring diagrams are just gibberish to me, so they are no help. I know enough to get in trouble and electrocute myself. The Service Manager at the local bike shop said it was OK to cut it off, but he didn't sound like he knew what he was talking about. He didn't even ask what year or model bike I had. I just told him I had an older VR.

 

The bike has been sitting in the back of my garage, since last fall, because of overheating problems, and not charging. Put the new stator in, in the fall and then lost interest because of the overheating problem. I have a GW, so there was no hurry to fix it. If I can get the R/R unit in and working, I might work on the overheating problem (long story) and if I can't, then I will part out the bike over the summer.

 

I have owned this bike for three years, but have only ridden it sporadically because of the overheating problem and now the electrical problem.

 

Thanks for any help.

 

Jim

[rhncue]

I have a 83 VR with an 86 motor (previous owner changed motor, instead of fixing 2nd gear) and have bought a heavy duty stator and regulator/rectifier from Buckeye Perf. and installed the stator OK and works good, but then noticed that the instructions for the R/R said to cut off the brown wire in the wiring harness and discard it. The R/R is a knockoff and not a Yama part. I am wondering what the brown wire is used for and if I can cut it off without any bad effects. Can I safely cut and discard this brown wire? Electrical wiring diagrams are just gibberish to me, so they are no help. I know enough to get in trouble and electrocute myself. The Service Manager at the local bike shop said it was OK to cut it off, but he didn't sound like he knew what he was talking about. He didn't even ask what year or model bike I had. I just told him I had an older VR.

 

The bike has been sitting in the back of my garage, since last fall, because of overheating problems, and not charging. Put the new stator in, in the fall and then lost interest because of the overheating problem. I have a GW, so there was no hurry to fix it. If I can get the R/R unit in and working, I might work on the overheating problem (long story) and if I can't, then I will part out the bike over the summer.

 

I have owned this bike for three years, but have only ridden it sporadically because of the overheating problem and now the electrical problem.

 

Thanks for any help.

 

Jim

 

If the directions say cut the brown wire then do it as it's not needed. the OEM regulator used it for feed back from the ignition but most after market reg/recs don't use them.

 

Are you sure the bike runs hot? The gauge on the early models are not calibrated correctly and read hotter than the bike actually is. However, if the bike is running hot there is two things to check. One is the thermostat and 2nd is the impeller on the water pump. The early bikes use a plastic impeller that can break or start slipping causing over heating problems. It can be replaced with the upgraded metal impeller.

 

Dick

[Jayceesfolly]

Dick:

 

Thanks for the reply on the wire. As far as the overheating goes, I am aware of the gauge inaccuracy. I have had to re-wire the fan to add a manual switch to keep the bike cool. Running in city traffic, it will overheat, even with the fan on. It will boil over into the overflow bottle at ambient temperatures over 75 degrees. The gauge runs in the red (just over the green) when cruising at 65 MPH on the open highway. As long as I am moving, it doesn't boil over. If I run down the highway and stop for fuel, the bike will overflow the tank and spill at least a quart or more on the ground. I don't really ride the bike when the ambient temp is over 8o degrees. I have replaced the rad cap w/a auto (I think a #156) one, and have had the radiator cleaned and pressure tested. Also, new thermostat (auto type - can't remember the #) I got those numbers from the other Yamaha site. The only thing I have not done is pull the water pump. I just picked up a used cover and impeller assembly and am going to take mine off the bike tomorrow and see if it is a plastic or metal impeller. I thought I read somewhere that the 86 motor had a metal impeller, but am not sure what is on this bike. I plan on tearing it down tomorrow to see what it looks like. I know the impeller is rotating because I can see the fluid moving past the open neck on the radiator, just how efficient the impeller is, I can't tell. The drain knob is in the 2 O'clock (the "off") position and the bypass hoses are not plugged. At this point, the only thing that it could be is the impeller gone bad or the hoses are collapsing under high RPM. This bike has been sitting in my garage for two or three years and it is time to fix it or get rid of it. If I can't fix the overheating problem, I will probably part it out. I have a 89 GW that I ride but I like the VR because it is a faster bike and a lot more fun on the twistys.

 

Jim

[jasonm.]

Yes, the '86 has metal impellar. But it's easy to check by pulling the round cover off. If you are over heating and you have a good cooling system as your tests suggest... Then you likely have the engine WAAAAY out of tune. Or something you are saying you think is true(thermostat good, etc)...may be not so true. What are you seeing for MPGS on the hi-way? You should see 35mpg+ all the time. Oh, the brown wire is the "sense wire". It is switched on w/the ignition, it detects the voltage in the system and TURNS ON the R/R along with giving a reference to regulate the voltage. FYI, should the brown wire not be connected and is needed...your charging voltage can go to 17vdc.

[Jayceesfolly]

Jasonm:

 

Thanks for the reply. Both the new and old thermostats were tested in a pan of water with a thermcouple and both opened @ 180 F, so put the new one in and still have the original. I also noted increased water flow past the filler neck when the thermostat opened(w/rad cap off). The only other thing I can think of is carbs not synched , but MPG is around 40 and is consistent, so it can't be too far out of tune. The motor idles very smooth and has good power, no hesitation on quick acceleration and pulls smoothly right up to 70+ MPH.

 

After checking the impeller tomorrow, and replacing the R/R, I will take it to a local dealer to have the carbs synched and have everything checked over.

 

Has anyone added an oil cooler in line with the radiator to increase cooling capacity, as I have a couple of oil coolers that could be adapted?

 

Thanks for your help, jasonm.

 

Jim

[jasonm.]

I USED TO HAVE AN OIL COOLER ON MINE. But that's when I pulled a trailer cross country. The cooler adapter I used came from and XS1100 series lockhart cooler. I do NOT recommend an oil cooler because the cooler and fittings limits MAX. oil pressure when engine is hot. Don't do it. Trust me on this. Better to just get a cooler thermostat. That's what I did.I have a stant 227 rad. cap on mine. Also make sure you did not put the thermostat in upside down. Correct is , "Point faces UP". ANd get a an infrared thermometer. You can find them cheap sometimes. Just point and shoot. It won't lie. I honestly think you have a crudded up radiator.

[Jayceesfolly]

Jasonm:

 

I will get a lower thermostat this week, do you have a part number and what is the temp rating? 160 F ? I changed the thermostat last year and I am pretty sure I oriented it in the right direction. As long as I am doing that, I might as well put another radiator in it. I have a spare one. The original radiator in the bike now has been pressure tested but not cleaned so it may be plugged up. But looking in the neck, the fins that can be seen, look very clean.

 

I am replacing the R/R tomorrow morning and want to know if I can put it on top of the airbox, with double tape rather than take the old one out and re-installing in the original location. Seems like a lot of work. Will the R/R get enough airflow to keep it cool when it is installed on the top of the airbox?

 

Thanks

 

Jim

[jasonm.]

I don't have a part # . BUT, DO YOU HAVE THE original thermostat? If yes...then there is a screw in the middle. Use a good fitting screwdriver. It will be stiff to turn...steel screw against the brass...it will turn. TURN it CW till it's flush then recrimp. NOW you have a 165 thermostat. This can be done with most thermostats. They are set this way when made...just to whatever spec./temp is required. Must be a brass T-stat. Mine runs very cool all the time. Rarely higher than "4 o'clock". Also I just thought...CHECK the plastic drain cock below the radiator. If not set correctly...you could possibly run hotter than normal...I think. But not overheat like yours has been doing.

Edited April 19, 2010 by jasonm.

[Jayceesfolly]

I have the original thermostat and will modify it and put it back on the bike on Friday. Plastic drain cock is in the 2 o'clock position, I am aware of the confusion over the correct position the knob should be in.

 

Thanks for your help.

 

Jim

[frankd]

Is your engine clean?? Especially the oil pan?? Before I pulled my 83 down for the 2nd gear repair I was starting to have overheating problems when it was over 90 degrees out. After I put it back together, it ran much cooler. The only thing I did that would have affected it was to clean the engine. Before I did it, the pan was extremely dirty and packed with crud. The radiator doesn't dissipate all of the engine heat.

 

Frank D.

[Jayceesfolly]

Jasonm:

 

Modified the original thermostat, as you suggested, and put the unit back in the housing and then discovered the spare radiator has a broken pipe connector on it, so I had to use the original radiator. Anyway, put everything back together and went for a ride yesterday. Still overheats. The only thing I haven't changed is the rad, so my guess is it is plugged up. I am going to take my spare radiator to a radiator shop and see if they can re-core it and fix the broken pipe.

 

The electrics work fine now. I have 13.3 volts measured across the battery @ 2500 rpm.

 

Frankd:

 

I have never had the oil pan off and really don't know how to get it off. I don't have any way to raise the bike to remove it, and have no desire to lay on the garage floor! So, checking the oil pan will be a last ditch thing to check.

 

Thanks, guys.

 

Jim

[frankd]

Maybe you mis-understood what I was trying to say......How clean is the outside of your engine, especially the oil pan?? When you are going down the road, the air passing over the engine disipates a lot of heat. Before I pulled my 83 to do 2nd gear, the underside was cruddy and it overheated. After it was all cleaned up, I had no problem at all.

 

Frank

[Jayceesfolly]

Frank:

 

Yes, I misunderstood what you were trying to say. The oil pan has not been cleaned since early last year. I scrubbed it down, last Spring (one year ago), with Simple Green and a paint brush, then rinsed. Haven't touched it since. I will look at it this weekend.

 

Jim