What's the purpose of a case saver?

[fabiodriven]

Hey that looks good Mike! JB Weld?

[Big Mike]

It is Putty Weld, made by JB Weld, so much easier to work with in this instance that regular JB weld would have been. Thanks Fabio, Fixed the case and replaced the outer cover. Case Saver and cool Sprocket Cover that I won at T'Fest go on tonight.

[wisconsinite]

They protect the cases on a Honda which will inevitably habitually throw the chain into the poorly designed clutch shaft that sticks out in its path. A swingarm chain guide is money equally well spent, but having both is the best insurance.

On a Yamaha they serve no functional purpose, but they look pretty, and buying them helps out those who make and sell them.

i must respectfully disagree with you sir, and if need be can produce photographic evidence of a quite damaged tri z engine case

[ps2fixer]

Have to support the idea of a case saver, never knew there was even such a thing till I bought a parts engine for my 250x, oh boy did I need one for my 99 Yamaha Warrior... it has a crap rtv repair on it to keep from leaking, but it don't run atm anyway lol.

[TimSr]

I'll back off from the "Yamaha" claim which was too general, as I really can't speak for the thumpers and some of the quads. I'm mainly talking about the TriZ, Banshee, and Blaster which use the same type chain guide system.

First, I had a TRX250R for 4 years, and can't tell you how many times I threw the chain. Jr has had his 86 ATC250R about 5 years, with multiple chains being thrown, and one case weld job, after twice doing damage WITH a case saver. I've been riding TriZ's since 1990 in some of the worst conditions known to man. Number of chains thrown in 22 years is 1 if you count the time I lost a master link. Thats a lifteime for many of you! My brother has run his banshees since the first model came out in 1987, in even worse conditions than me. Number of chains tossed since 1987 = 0. He has run a Blaster since 1993 which Jr owns today. Number of chains tossed on this Blaster since 1993 = 0. My first objective was not, "how do I protect the case", but rather,"how do I keep this stupid Honda from throwing chains". Case savers are nice on your Honda, but a Yamaha style chain guide is better insurance.

Now lets look at what happens when you do throw a chain on a Honda. The clutch pivot shaft sticks way out about an inch or so directly covering the entire patch of the chain as though it were placed there just for catching and wadding tossed chains, which it always does.

Then look at your TriZ where the clutch pivot shaft is barely in the path of the inner side plates of the chain, which deflects the chain to the side of it if you have the extremely rare misfortune to actually throw one. If you add a case saver, you actually increase your risk by creating a surface for your chain to catch on, and wad up inside of, and crack the case where the case saver is counted. But as I said, that risk is minimal since its extremely rare to toss a chain to begin with. I do however recommend removing that plastic front spocket guard if you have one, which also serves as a wad up guide.

I do have some TriZ cases with what looks like chain damage which amounts to grooves in them. I have doubts as to whether its from thrown chains, or it was just a chain carrying mud and acting like a belt sander. Maybe a case saver could help in that respect. I guess everyone should use their best judgement for their own situation, and I hope you get the results that I have.