Warrior problems

[2000chevy]

OK so I did some trading and ended up with a Warrior. I was told it needed put back in time and it would run. I went to put it in time and pulled the cam gear cover off and discovered that the gear had a crack in it. I went to pull off the gear and found that the little pin that holds the gear in place broke off in the head. Now here's my questions 1. What all could be damaged being that the pin broke off 2. Could I just weld the bolt and the gear together to fix this I know its probably not a very good idea, but its not in good shape so if I could just get it running and keep it running it'd be good enough for me and keep the cost down as much as possible

 

[Larry's Shee]

1991 Yamaha Warrior 350 YFM35XB Parts, 1991 Yamaha Warrior 350 YFM35XB OEM Parts - BikeBandit.com

What I'm seeing is that #3 aligns/times #2 with #1. You would have to be dead certain that it's properly ligned up. However, once welded it will be a mofo to fix properly.

Odds are that something drastic happened to break that pin and crack the gear and welding $hit up won't fix the problem, only make it worse. My guess is that it slipped the time chain and a valve struck the piston. The best way would be to remove remainder of pin and get another gear.
Better yet would be to do MORE diagnostic on it first. Back the valve adjusters all the way off and see if the cam turns. Get good parts, time it, adjust valves, and see if motor turns over without pieces hitting.

 

[2000chevy]

Never mind about the welding thing I found a friend with a big bear 400 that has a good head and gear assembly on it. Does anyone know if the heads are a direct fit? I did some research on it that said you could do it but I'd like to hear some input from you guys

 

[jus_me]

well with the head being larger you would have to use the big bear timing chain.. as far as if everything else will line up im not to sure.. using the big bear head will also lower your compression.. if the oil channels line up and all it may work with some mods, but seems like a lot of trial and error and checking and rechecking to make sure all lines up correctly.. Imo if its just a beater quad and your not going to fix it with the proper warrior parts and your not going to really put any $ into it and your getting the other parts for free and you have plenty of time on your hands, give it a shot,, worse can happen is u damage it even more than what it was before... but for experimenting give it a shot it might possibly work..

 

[Larry's Shee]

O, I assumed the 350 and 400 head were same by how it put it, lol. Just look for a used warrior head if they aren't the same.

Usually very hard to "fix" something for nothing.

JMHO, your results may, and will vary.

 

[2000chevy]

I think the only differences between the 2 motors is that the big bear has the longer stroke. I think that the bores might be the same but I've helped working on his big bear and the motors do look pretty similar on the outside. I also looked at a moto 4 350 and the motors look almost identical on the top end. I would figure that the valves would be slightly different. I'd rather try a head off of another Yamaha 350 but I'm going to give the 400 head a shot soon so I'll let you guys know. This will probably be my last 4 stroke project lol I would rather work on 2 strokes

 

[2000chevy]

Ok guys. Got the 400 head today and put them side by side and did some comparing. The two heads are almost identical. the only difference I can see is the middle hole on the very outside just below the timing sprocket cover on the outside. Ill let you guys know how everything goes when I get enough time to put it together