2000 Yamaha Big Bear

[Gwbarm]

I am new to 4 wheelers but I just picked up a 2000 Big Bear YFM400FWN cheap. He said it had wiring issues don't know what the problem was before he kept saying it needed a new wiring harness. Well it does now the complete harness was out of the bike. I do have the old harness but really don't know where to start. My thoughts were start with a new harness but so far has been unobtainable. Any of you guys know where to start. Im ready to go back to the basics fire, gas and compression to get it running to see if engine and tranny is good, before sinking a lot of money into electronics, anyone have any ideas 

[Mech]

Inspect the loom for any signs of chafing, then check at the ends of the wires where they go into plugs looking for dirty/corroded connections, and wriggle the wires just there looking for any that flex too easily, indicating the wire's broken inside it's insulation.

All of the electrical component tests are spelled out in the manual.. Most of the testing you can do without the bike running, using an ohm gauge.

After you've made ten posts you can download a manual from this site, up the top, in "More", then "atv service manuals", which takes you to a new page, in the new page on the right and down a bit you choose your make.

[Mech]

Once you have the manual, you could trace every wire using an ohm gauge to check for continuity from one end of each wire to the other end.

[Gwbarm]

Thanks members for the vote of confidence I am really overwhelmed right now . I am an older guy I thought I could fix anything until I saw this mess of wires. I mostly work on 60s Jap bikes they are easy battery ,spark gas compression. This is my first 4 wheeler and. I also have a Suzuki Eiger that I got right after that on a trade trans locked on it. Thanks again ! 

[Gwbarm]

How do you know which model Big Bear you have, I didn't know there were so many different models in 2000, I think mine is aYFM400FWN the only reason I think that is from a vin# internet search before I found this forum. Thanks!

[Mech]

I generally look up a parts place online and start comparing parts. Some parts places when you look up a part, will tell you what else that part fits. So.. if you look up your brakes, and fuel system, and transmission, and then check what other models have those same combination of features, that narrows it down often, then you could look up seats and bodywork, speedo, lights..   racks,  electrical parts, carbies are a good one to check, they vary a lot with markets and years..

[Gwbarm]

Thanks! I did download the 2000 big bear, kodiak manual it was showing a water cooled engine mine is not water-cooled so that may not be the right manual. I thought all big bears were air cooled. It may not make a difference if all the wiring and components are the same.

[Mech]

This looks air cooled...

https://www.manualslib.com/manual/659758/Yamaha-Big-Bear-4x4.html?page=10#manual

The pages load quickly if you want to preview it before downloading..

[Mech]

Older model but it may be the same..

https://www.manualslib.com/manual/998189/Yamaha-Yfm400fw.html?page=2#manual

[Gwbarm]

Thanks ! They may be all close to the same wiring. The manual I downloaded from this site said 2000 big bear/ Kodiak maybe the kodiak is water cooled. 

[davefrombc]

The Big Bear 400 is air cooled and the Kodiak 400 is water cooled  according to their specs I found on line .

 

[Brantley11]

Besides the electrical problems i always disliked the u joints and such for the 4x4 system. They were always difficult to access and replace.

[BruceWA]

I picked up a 2000 Kodiak and have been doing lots of repairs.  A good manual is important. When wiring, I agree that a good ohm meter is a must!  Removing body parts makes access a lot easier. Be sure to run and secure all wiring correctly m, especially around hot areas (cylinder head, exhaust, etc.)

 

[ceedaman]

I second the routing as BruceWA said. I rewired my switch and ran wires to the fuse box of the bike because the previous owner ran it too close to the exhaust... It shorted out and caused even bigger problems. 

[Gwbarm]

Thanks I appreciate the response, I've been looking for a new wiring harness the one I got with the bike is so chopped up, I may just rewire it myself, I've been trying to figure out how to power it up from the battery to see if it runs might have bad cdi or other problems .