NC31/NC23E Starter Motor Replacement Procedure

[zen61]

Does anyone know the correct procedure for replacing the starter motor in a cb400 NC31/NC23E?

I have seen instructions for the CB-1 which involves tank removal. But from what I can see with the NC31 is that it looks like you would need to remove the tank, airbox and quite possible the carbs and even some of the cooling hoses to get to the starter motor on one of these--sheesh?!?!?

So, I am definitely up for any hints anyone has about how to approach this.

I'm looking to go with a CB-1 Mitsuba SM-13 which appears to be the same as that used on the NC23E engine.

In fact at one site http://www.asist-world.net/page088.html I looked at it appears that this starter motor was used on a range of bikes including the CBR400RR, CB-1, CB400SF, and the Yamaha TT250R.

Now if only I could work out the best/most efficient way to get it out and back in?

Any ideas?

Cheers...Zen.

[thunderace]

I'm afraid it means removal of the tank, airbox and carbs, there's no way around it. It's the same procedure with most bikes.

[zen61]

B*gger!! Looks like it will need to go to the shop as I don't fancy having to put all of that back together--especially the carbs.

Cheers for the info.

[thunderace]

It's pretty simple to do. The carbs are just undo the rubbers and pull them off as a complete bank, no strip down involved. If you're not 100% confident, take plenty of photos of each fixing point and make plenty of sketch notes as you take things off. Make notes of bolt sizes and where they go, etc.

[zen61]

Alright then I'll give it a go. And thanks for the advice about taking photos so I can get everything back together again.

...and if it all goes pear shaped then I can take it to the shop or buy a VTR1000 :D

Cheers...Zen.

[CMSMJ1]

As the man says - it is easy.

It all comes off in obvious, easy to do bits and goes back the same.

If you can tie your laces you can do it..

[Superjack44]

When you undo the carb mounting rubber clips just work them up and down while excerting rearward pulling pressure,dont do as I did and try and lever them off with a lever that slipped behind one of the mixture screw fittings .
The airbox/battery box once the bolts are removed should move back enough to remove the carbs.
Sound advice from NC31/NC23E

[tomigun]

Just a tip.When you go to pull back the carbs,do it with warm engine.Otherwise you will try for ages:
http://www.youtube.com/watch?v=a74tiqyo7PI
But with warm engine the rubber mounting rings get softer and it's easy to pull out the curbs.

[amorti]

I swoosh a bit of red rubber grease (silicon grease is fine too but NOT mineral grease!) around the rubbers, that way they go on easier and will also come off next time. Similar precaution to putting copperslip on a bolt that was tough to get out to make it easy to put in and get it out next time.

[zen61]

We'll I finally mustered the courage to do the job. Wasn't expecting to have to remove some plumbing to get access to one of the mounting bolts. I made videos of the whole process which I'm separating into different sections and will upload shortly, inc. tank removal, carb and airbox removal etc.

For now I have uploaded the first vid which demonstrates fitting a carbon brush kit to the Mitsuba SM-13 starter motor on the CB400 (NC31). Hope someone finds it helpful.

http://youtu.be/0yCW0G93FxU

More to come over the next week hopefully. Thanks to all for the great advice especially about photographing/videoing the process as it came in handy when I couldn't remember the order some things went back together.

Cheers for now...Zen