Charging issues/SH775 question

[Guest]

Hello all,

I have an '82 G450L. I just replaced the battery, since I've had to push start it the past couple of days. I have a DC voltage meter that I installed after a harrowing freeway trip in the rain resulted in my starter button spring failing and draining my battery intermittently... nothing like having a state trooper watch you push start your bike on the side of a 5-lane interchange heading into a city.

So, after installing the gauge, on my morning commute I'd see it hit 15v at red lights and do what it's supposed to, until the past week or so. Now it never really hits 14v. On top of that, there wasn't enough kick to get the starter turning in the morning - so I chocked it up to damage/age from the freeway debacle, plus the colder weather.

Now, however, I've done the quick test and I'm not charging how I should be.

Here's my question: I'm broke (who isn't), and this bike is my primary vehicle. I bought, hastily and without paying much attention, this summer a cheap SH775 off ebay, then realized after it had shipped that I had paid way too little for a new part. Will the "counterfeit" SH775 still work? If it doesn't, what will happen - will I lose my leg in a fiery explosion, or will my bike just not charge properly (which I can monitor on my handy in-dash voltometer)? If it's the latter, I think I'll risk installing it this week and see what happens.

Thoughts?

Thanks!

 

[Nessism]

15V is too high. The ignitor will fry, which is a very common 450 issue. The ground for the R/R goes though the battery box or a small bracket at the back which is prone to corrosion and when that happens, the voltage spikes way high. I'd check the ground path for the R/R and fix it up. You should see no more than 14.5V at 5000 rpm otherwise the system is over charging. I'd keep the stock R/R as compared to the fake SH775 if you can get the system under control. One issue: if the battery is weak you can't perform a proper charging system test. Get it fully charged, fix the ground, and then go from there.

 

[roeme]

- Let's hope your dash voltage meter shows a little bit too high.
- Can you take some pictures of your SH775 and show them to us? Maybe you've been lucky.

If counterfeit, your R/R most likely will "just" be a relabeled shunting R/R. So you won't get the benefits of the SH775, but neither will it destroy your bike. Before replacing, follow Ed's advice.

 

[Guest]

I bought a new battery as part of the diagnostics. New, possibly counterfeit(?) SH775 is charging perfectly to 14.5v and no higher. Starter kicks better with cleaned up grounds (and some wiring refresh - soldered a new wire onto my starter relay since the original look worn out).

The SH775 I have is big and appears to have the right dimensions, and doesn't look super cheap, or feel super cheap. It doesn't have any markings on the outside, however. I'm going to assume it is just a cheaper knock-off version - maybe it's shunting, but either way everything should be fine.

I do think the old R/R was hitting 15v... probably why it no longer does its job. I had my gauge running off a trickle charger cable that had been installed, and the ground and positive post were both pretty clean.

Are the symptoms of a poorly functioning ignitor poor running/misfires? Or is it involved in the starting procedure? I guess I could just google what an ignitor does - I'm more familiar with 90's vehicular electronics and technology, and on cars for that matter. (Looks like it works to clean up/adjust the spark with the coils? Interesting)

Thanks for your responses! Forums like these are the lifeblood of old motorcycles and cars.

 

[Grimly]

To the best of my knowledge the knock-off 775s are simply shunt units internally, so you're back to square one, with a limited-life stator.
Best of luck with that.