First start since 1989 tomorrow!

[Membername]

So I've got the bike put back together, brakes bled, transmission oil in, 2-stroke oil in, 50-1 pre-mix with oil pump.  I'm going to start it tomorrow for the first time in 30 years.  Any hints or tips for a first start after rebuild (I didn't split the cases).

Karen

[Hawaii-Mike]

Are saying you put premix in the gas tank?

[Membername]

Yep, just until I confirm the oil pump is working well.

[IICYCLE]

If it was me, i'd do a leak down test.

[Evans Ward]

I like to prime the oil lines from pump to engine with a syringe prior to start up then manually advance oil pump cam by hand once it fires up to ensure max flow of oil injection too. I usually hold it wide open for about 30 seconds or so on initial start up.

[Membername]

It passed the leak down test.  Good idea on the oil pump lines Evans.

K

[Czakky]

How's the timing/points?

It looks great btw.

[~JM~]

It looks great btw.

It would look much better in my garage.

[svgarage]

An exciting day indeed! Be sure to post a video!

[Membername]

The points are new and bike is timed to 2.0.

Ok the good news is it actually started.  The video below shows the first start (my uncle started it).  It dies in the video because the idle was set too low. 

https://youtu.be/UtZ52uAuQf8


The bad news is even after the idle was set correctly, it still dies after running for a few minutes, and then won't restart unless the battery is recharged.  So I guess either the battery is bad, or it needs to be charged fully, or there is an issue with the bikes charging system.  I'm trickle charging the AGM battery overnight and will then start it again and measure the voltage on the battery at idle lights off (12.5 +/- 0.5) and at 3000rpm with lights both on and off (14.5 +/- 0.3).  If the first is wrong it is the battery, if the second is wrong, it is the charging system.  Does this sound like the correct course of action?

My understanding is that the battery will not charge under 3000rpm is this correct?  But even so the battery should not become depleted just idling, right? 

Karen

[SUPERTUNE]

Oh love that sweet sound of a stock RD400!    
To start a cold RD, turn on gas, wait 30-45 seconds, turn on choke, NO THROTTLE, NO KEY ON, give 2 full kicks, now turn on key and check toggle kill on handle bars as they get bumped to the off position a lot. Always good to keep the headlight switch off as well, this insures you get good voltage to the ignition coils. (see my comment below)
Hold throttle barely open then kick to fire up! 
Big hint that I see with your uncle starting the bike... is he's opening throttle as he kicking through...if the throttle goes open the carbs can't pull up the fuel from the float bowls. Just hold at barely open and steady.

Make sure the battery is new, Yamaha Zuma 50 AGM works very good.
RD400's will start charging about 2100 rpm and full in by 2800 or so...we use 3000 as a base.
Battery does have to have a good charge of about 12.6v min and no less than 12.0v with lights and key on.

This is where doing coil relay mod helps stock wiring RD400's immensely!
I need to repost another "how to" again.
Very happy for you Karen! You did stay the course and got it done! 
Chuck

[paul1478]

GREAT looking bike. From the photos it looks about new.

[Organicjedi]

The points are new and bike is timed to 2.0.

Ok the good news is it actually started.  The video below shows the first start (my uncle started it).  It dies in the video because the idle was set too low. 

https://youtu.be/UtZ52uAuQf8


The bad news is even after the idle was set correctly, it still dies after running for a few minutes, and then won't restart unless the battery is recharged.  So I guess either the battery is bad, or it needs to be charged fully, or there is an issue with the bikes charging system.  I'm trickle charging the AGM battery overnight and will then start it again and measure the voltage on the battery at idle lights off (12.5 +/- 0.5) and at 3000rpm with lights both on and off (14.5 +/- 0.3).  If the first is wrong it is the battery, if the second is wrong, it is the charging system.  Does this sound like the correct course of action?

My understanding is that the battery will not charge under 3000rpm is this correct?  But even so the battery should not become depleted just idling, right? 

Karen

Almost there! Keep us posted.

[Membername]

Well, this morning before work the battery (not hooked up), after trickle charging all night was at 12.87.  So I hooked it up and went to work. Then:

After dinner, key off: 12.81
Started on first kick (my first ever start  )
Bike idling: 12.8
Bike at 3000rpm: 12.1
Bike at 3000rpm headlight on: 11.8. 

Also the fuse on my multimeter blew but maybe that was coincidental, not sure. 

So I guess I have a charging issue?  Any help appreciated. 

Thanks,
Karen

[SUPERTUNE]

Yes, it sounds like not charging at all or missing a leg or 2 from the stator.
You can call me and I can talk you through some checks to see where your issue is, until I have some time to post up a lengthy "how to".
First three things to check is 3 white stator field windings/and the connector to the harness and plug at the rectifier, the rotor winding/brushes and the rectifier with 12 different resistance checks.
(involves polarity checks)
I never have had to replace a voltage regulator on a 400 system.
(the stock 400 system is 2 separate units, 1) rectifier and 1) voltage regulator, not a all-in-one)
Chuck