TW200 Forum banner

1 - 10 of 10 Posts

·
Registered
Joined
·
43 Posts
Discussion Starter #1
I just got my TW last friday, and have been working the bugs out of it and need to know if this is normal.

It does not have a battery in it right now (it is coming just not here yet). Just been kick starting and riding. One thing I notice is when I rev the engine the lights dim. Everything works fine at idle. But when the rpms go up all lights dim. Just need to know if I need to think about getting a replacement regulator/rectifier.

Thinking it may be the coil drawing all the power as it fires faster, that is the only other thing I can think would cause the lights to dim.
 

·
Registered
Joined
·
796 Posts
What year is your unit? There are at least three different charging systems. 1987 being the oddest.
I would agree it's sounds like coil draw. Those systems use the battery as a power sink any over current produced
goes to the bat ray. I'd wait on any conclusions until I had a bat ray and use a meter to measure voltage output.
 

·
Registered
Joined
·
43 Posts
Discussion Starter #3
It is a 1990. I was planning on waiting until I put a battery in, just thought maybe it was totally unusual. Anyone know the amp output of the 90?
 

·
Registered
Joined
·
2,663 Posts
The ignition system is totally separate from the charging/electrical system on these bikes, so it can't be "coil draw". Get the battery in it then go from there.
 

·
Registered
Joined
·
2 Posts
I dont know about the tw specifically but in my xr the regular/rectifier stablizes the voltage so it won't shoot up and fry your system when your rpm is high. In my friends tw, I noticed that the light is very dim on idle and brightens significantly when you rev it. If that were to happen on my bike it would indicate a bad battery or a bad regulator. I'm wondering if that's normal for a tw?
 

·
Registered
Joined
·
2 Posts
Thanks tommy.

As far as the op's q, I agree with others that you can get no accurate reading without a good battery installed. And again, I'm not familiar with your bike, but on my bike, riding without a battery puts a lot of stress on the regulator and could cause it to go bad, especially if you have a high wattage headlight and other add-ons. Let us know what happens.
 

·
Super Moderator
Joined
·
17,650 Posts
Mine is an 87 with the tiniest electrical system Yamaha made for the TW. My lights are dimmer at a low idle, but it's normal and I don't worry about it at all nor do I expect any problems. I don't know how the other years functioned, since they beefed up the electrical system after the first year.
 
1 - 10 of 10 Posts
Top