As I posted before I just bought an '88 LT500R from the origional owner about two weeks ago. He just put a new top end in it but soon after I got it I realized that the crank bearings were going bad. I replaced them and fired the old beast back up just today. It runs excellent! The clutch and transmission and everything work great! The only thing is that at idle it has a little bit of a knocking sound. Not terrible, just enough to concern me. I couldn't figure out what it was so I threw it in the trailer and took it to the local Suzuki dealer and had one of the mechanics take a listen to it. He said that it was just side clearance on the piston and not to worry about it. Since it doesn't make the noise at any other time than idle I'm pretty sure he's right. Has anyone else ever had this problem or have any advice/comments for me? Give me your thoughts. Thanks.

 

Well I went from riding a Stock Banshee to the Zilla and all i heard was loud sounds hehe. It definately could be piston 'slap' but it usually doesnt make a very loud noise, but if you do have piston slap, at idle is where you'll hear it. If it is the piston, then two possibilities. 1, the engine could run forever. or 2, the piston will crack around the skirts after a bit.

If you want to be really sure that this is what is making the sound then take off your cylinder and measure the bore and make sure you have the right piston size. Alot of people go for the cheap option when rebuilding the top end. Ive heard of people replacing the rings, going to the next size bore but using the old piston. this is where the piston slop or slap usually comes from. I would prefer to take it apart again, get it checked and new gaskets simply for the piece of mind. Nothing worse than going riding on something thats not running right. Hope that helps dude. [img]i/expressions/face-icon-small-happy.gif[/img]

Also do u have any pics of your zilla? Ive been collecting pics of the great beast and any additions would be great!

 

It does have a brand new piston and rings. I checked it out when I replaced the crank bearings. Funny thing is I took it down to my friends house to get his opinion and it stopped doing it completly. That's typical though. I'm going up to the dunes this weekend. I'm confidend everything is in good shape (famous last words huh). I don't have any pics yet but I plan to take some and I'll send you some when I get them. Thanks.

 

Do you know whether the rebuild was done by a shop or by the previous owner? it is possible that the incorrect size piston is in it. When i got my cylinder's sent out for re-boring (Banshee), they then selected a set of Wiseco's to suit the bore. Id just check the compression and if its ok, go riding. Peace[img]i/expressions/face-icon-small-cool.gif[/img]

 

Zillaman

My 87 zilla makes noise at idle. In fact it has been making noise at idle for years. It is very unnerving to just leave it alone, but I do. I've had the cases apart a couple of times and have replaced parts, but the noise continues.

 

My quadracer 250 made a knocking noise when I bought it, everyone told me it needed a rod kit, I road it all last year it ran fine. I rebuilt the top end and had it ported over the winter, after it was broken in I was getting on it one day, I shut it off and started it again, the noise was real loud, so I pulled the motor and sent it to the Suzuki dealer they said it needed a rod kit, I had them change the crank bearings and water pump also. When I put it back together it had almost the same noise as when I bought it. The noise has subsided to where you really have to listen for it now, after 20 - 30 hours. Bottom line is I wouldn't worry to much about it.

 

Well just to inform you all I just returned from my day at the dunes and the 'ole Zilla ran marvelous. It ran so good that when there was a group of quads sitting around this big water hole deciding who was gonna be the first to try and hydroplain across it. Well it seems the guy with the high flotation front dune tires and wide paddles on the Quadzilla had the best machine for the job and was nominated. That would be me of course. To make a long story short I made it across (about 50 ft.) but coming off I hit a stick that was sticking out of the water (this is in 4th gear wide open), knocked my front tire off the bead and sent me flying as my precious Zilla went tumbling. I'm pretty banged up with a severly sprained or broken ankle (going to see doc. on mon. of it doesn't start getting better) and some pretty good bruises. Darn stick! It could have been a lot worse though, I was going pretty fast when it started tumbling. Thankfully other than a couple tires nocked off the bead the ole Zilla is ok too. We'll heal up and check for sticks next time and get our revenge on the water hole. See ya guys.
.