Rusty sprocket cover bolt

[pzkpfw]

So yesterday I pulled off my sprocket cover, to clean chain spoodge out from inside, before cleaning and oiling the chain and adjusting the tension.

Of the four bolts holding the cover to the engine case, one was quite rusty (this on a built in 2005, ridden since 2006 bike (far fewer k's than some bikes)).

The bolts were about 6mm diameter, about 70mm long, with thread on just the last 20mm.

Just one of the bolts was very rusty, along most of its length, the other three seemed OK (mostly just a little corrosion visible just under the head of the bolt). There were no washers on the bolts or gaskets on the cover; it was all just metal-to-metal contact.


Is this kind of rust "normal"?

What's the best thing to do in this case?

(I had to get the bike ready to ride to work, so quickly just gave the bolt a good scrub with a cloth, and sprayed it with a little CRC before reassembling it all.)

Cheers,

[blackdog]

What's the best thing to do in this case?



Cheers,

It's just a bolt. Replace it.

[HenryDorsetCase]

you did what I would have done. maybe a wee smear of grease next time or copper grease. I love copper grease.

[unstuck]

It's just a bolt. Replace it.

And maybe a wee bit of high temp silicon around the shaft of the new bolt.

[FJRider]

Just one of the bolts was very rusty, along most of its length, the other three seemed OK (mostly just a little corrosion visible just under the head of the bolt). There were no washers on the bolts or gaskets on the cover; it was all just metal-to-metal contact.


Is this kind of rust "normal"?

What's the best thing to do in this case?

(I had to get the bike ready to ride to work, so quickly just gave the bolt a good scrub with a cloth, and sprayed it with a little CRC before reassembling it all.)

Cheers,

No gasket is necessary, as there is no oil seal required. No washers (spring or flat) for the same reason.

Yes it CAN be.

Take it (the bolt) to a engineering shop and buy stainless bolts of the same size. (THEY wont rust)

CRC is only a quick fix ... within a week it will be rusting again. The CRC will evaporate ... as it is NOT an oil ... or oil based.

[Howie]

CRC is only a quick fix ... within a week it will be rusting again. The CRC will evaporate ... as it is NOT an oil ... or oil based.

That Depends on which CRC product you are talking about! Lets assume you mean CRC5-56 Aerosol, which can actually be upto 30% mineral oil acording to CRC's own MSDS (http://max.chemwatch.net/cg2/minimsds.exe?&mode=SAP&ghsnotice=Y&cwno=4552-27&PASSOP=checkpass&user=crcnz&pwd=vAjbcD) sheet. If you use the bulk version of CRC5-56 the only product it mentions is "distillates, petroleum, light, hydrotreated" or in other words a Low odor paraffinic solvent such as Dearomatized kerosine or Deodorized kerosene. So if your use the aerosol version chances are it has some mineral oil in it.

I do agree though FJRider that it is not the best rust preventitive that can be used.

[pzkpfw]

Thanks all.

I guess I was just surprised that the bolt would end up rusting like that. Seemed like a design flaw or something.


If I replace the bolt, and reassemble with grease - does the grease go along the whole bolt - including the threaded part? (Will that affect the torque setting?)

Or do I just grease the shank part, as a water-seal? (Like with the silicone suggestion.)

[FJRider]

Thanks all.

I guess I was just surprised that the bolt would end up rusting like that. Seemed like a design flaw or something.


If I replace the bolt, and reassemble with grease - does the grease go along the whole bolt - including the threaded part? (Will that affect the torque setting?)

Or do I just grease the shank part, as a water-seal? (Like with the silicone suggestion.)

When the bolts are galve coated by the thousands each day ... the quality control tends to drop a bit.

You can buy COLD galve paint ... would do the trick ....

Loctite the thread ... will be easy to undo NEXT time ....

[The Pastor]

buying a new bolt will prob be around $10-20 per bolt. (they are custom made by kawasaki)

you can buy a generic bolt (has thread the whole way down) for far less, probably cents per bolt.

I dont know if there is anything wrong with the generic ones, but i use them all the time.

[Madness]

..........

What's the best thing to do in this case?

.........

It's a sprocket cover bolt. Forget about it or fit a replacement bolt. Ride.

[jellywrestler]

So yesterday I pulled off my sprocket cover, to clean chain spoodge out from inside, before cleaning and oiling the chain and adjusting the tension.

Of the four bolts holding the cover to the engine case, one was quite rusty (this on a built in 2005, ridden since 2006 bike (far fewer k's than some bikes)).

The bolts were about 6mm diameter, about 70mm long, with thread on just the last 20mm.

Just one of the bolts was very rusty, along most of its length, the other three seemed OK (mostly just a little corrosion visible just under the head of the bolt). There were no washers on the bolts or gaskets on the cover; it was all just metal-to-metal contact.


Is this kind of rust "normal"?

What's the best thing to do in this case?

(I had to get the bike ready to ride to work, so quickly just gave the bolt a good scrub with a cloth, and sprayed it with a little CRC before reassembling it all.)

Cheers,about six mm? it will be six mm what size hex has it got or is it a cap screw?
i'll have a whizz through my bolts and may have spare

[pzkpfw]

about six mm? it will be six mm what size hex has it got or is it a cap screw?
i'll have a whizz through my bolts and may have spare

Hey, thanks for that - do appreciate the offer.

But don't worry about it; it's my knowledge I'm trying to improve more than anything.

(I'll get to replacing the bolt when I have some time... I like the idea of replacing all four with allan-key type bolts (cap screws)...)

[FJRider]

Hey, thanks for that - do appreciate the offer.

But don't worry about it; it's my knowledge I'm trying to improve more than anything.

(I'll get to replacing the bolt when I have some time... I like the idea of replacing all four with allan-key type bolts (cap screws)...)

Replace with Stainless ones ... :yes:

[Laava]

Usually of the four bolts, one of them should be butchered so that it is impossible to remove with anything other than a cold chisel, one of them should be in a stripped thread section which is already cracked and falling away from the main crankcase casting and the other 2 should be mismatched and fingertight. If you are removing spoodge before refitting sprocket cover, don't forget to repack with spoodge of an equivalent quality and texture. Ham slicing machines have a suitable product around the base at the end of the week

[TOTO]

meh, just buy a honda that won't rust. those kawasaki things fall apart on you and the bolts start to rust from what I've heard.

[pzkpfw]

meh, just buy a honda that won't rust. those kawasaki things fall apart on you and the bolts start to rust from what I've heard.

Honda? Well, yeah, I did ask about lube.

[spanner spinner]

To answer your orginal question this type of rust is quite normal as only a very small amount of water drawn in around the bolt will cause this. There is never any gaskets ect as there are no liquids to seal in. If you do decide to use stainless steel bolts they will not rust but will seize into the alloy if you don't use a anti seize compound when you fit then due to the action of dissimilar metals. I have seen this on all models of bikes from 60k harleys to cheep chinese junk, even the mighty honda is not immune.

[unstuck]

even the mighty honda is not immune.

As I found out yesterday when I pulled the brake disks off the VF, 4 shiny new looking bolts and one rusty one.:yes: