Broken sprocket cover bolts

[kvgeorge1]

Stupid me! When I read the maintenance manual on my 2008 250R, I mis-read the torque specs for the engine sprocket cover bolts. They are supposed to be 87 ft-in, but I read it as 87 ft-lbs. Now, I over torqued 2 bolts, 1 broke off, the other I think is broken in the threads.

Now what? Do I have to get them professionally removed?

I am so mad at myself.

[Old_Six_Fitty]

Well, plus 1 for actually having the main manual and for using it.
Makes for a powerful lesson -don't over tighten the dam thing.

Don't sweat it too much, every mechanic has done this as well.

Did your break off one or more of the three mounting screws?



Fiche says these are 6mm x 20mm, 6mm x 25mm, and 6mm x 50mm
Flange head screws /bolts ...

1) Try to remove the stub of the remaining bolt -if any- using vice grips
2) If no stub is left to grab, then you need to drill out that little b~tch
--take off the final drive cover, being careful not to break anything else :^)
--take a small size drill bit, say about 1/8th inch
--carefully drill into the stub of the bolt and try to keep the bit centered
--drill in about 1/2 inch
--tap into this hole the extractor tool
--then use a wrench and back out the broken bolt

Sometimes the screw just strips the threads out of the case ... (swearing ensures)
If that happens you need to install a thread repair kit.

This might help orient you on the process ...
http://www.wikihow.com/Use-a-Screw-Extractor

[Ghostt]

Another victim of overuse of a torque wrench.

Do yourself a favor on by a good quality 1'4" drive socket set, save the torque wrench for the things that need it, which is almost nothing on the bike doing normal maintenance. I personally can't remember the last time I used my torque wrench on the bike.

As far as how to get those broken ones out, did they break flush with the surface of the block?. If so you'll need to get an easy-out, if your not familiar with them, let a professional so it, you could make the problem a lot worse.

But if your diehard wanting to use the torque wrench on everything, here's a chart that might help you out.

[kvgeorge1]

Thanks everyone for replying. I know for sure that one of the bolts broke off - how far into the threaded hole, I have no idea because I think I broke 2 and can't seem to back-out the other one I think I broke.

I agree with the torque thing. I thought I was being smart by torquing the bolts, but I was just being really stupid because I misread the manual and set it for foot-pounds instead of foot-inches.

That's what I get for being a noob at all this.

[DannoXYZ]

Here's decent screw-extractor kit I've used. It comes with left-hand drill-bits and about 1/2 time, drilling hole will back out the broken end. Otherwise, use the extractor and that'll remove it for sure! Nice thing about this kit is bits are sized properly for each extractor, so no guessing needed.

In certain extreme cases, I've welded smaller bolt onto broken one. Then I can use the hex-head to unscrew with socket.

[jkv45]

Skip the torque wrench on the small stuff like that, and just go "snug" with a 1/4" drive ratchet and a dab of blue Locktite if you want more security.

As far as the broke bolts go, post a photo if you can. Start by removing the cover and seeing how much is sticking out to work with.

Since the bolt is not seized or corroded, you should have an easier time backing it out. Sometimes you can use a sharp punch to spin it enough that you can clamp a visegrips on the end. If not, drilling and using an extractor is another option.

[kvgeorge1]

Ok, here's another stupid question - where can I find the bolts? I've been looking around and cannot seem to locate them. Is this something I need to special order from somewhere?

[jkv45]

Pretty sure those are shouldered bolts, probably M6s.

I'd personally get the OEM bolts, but you could find the exact specs ("M__ x __mm") and get replacements.

[kvgeorge1]

Where do you get your OEM parts - Kawasaki directly or is there a parts house that carries them?

[DannoXYZ]

Motorcycle shoppes typically have all those bolts.

Otherwise, I order from https://www.belmetric.com or http://www.mrmetric.com.
McMasterCarr has wide selection also; tends to be pricey.
I like MrMetric because I can place order in morning and go pick up.

Amazon also has large selection of metric nuts & bolts.

[jkv45]

Originally Posted by kvgeorge1

Where do you get your OEM parts - Kawasaki directly or is there a parts house that carries them?

I guess I'd call the local Kawi dealer if you have one close and see how much they want for what you need. It would be a bit more than the online cost, but you shouldn't have to pay additional shipping.

You can find the OEM bolts online also, but may end-up paying more in shipping than the actual bolts.

If you want replacements that are not the exact oem black shouldered bolt, you could check out a local hardware store once you know the exact dia and length you need. Some carry socket head cap screws that would work. Stainless Steel is always nice for anything that gets wet.

[Ram Jet]

Originally Posted by kvgeorge1

Where do you get your OEM parts - Kawasaki directly or is there a parts house that carries them?

If you want exact replacements - Partzilla.com. You might try Lowes or Home Depot or Ace hardware. Three stainless steel Allen head cap screws would be cool. Plus if you reinstall them with the typical Allen wrench there's little danger in over tightening them.

Bill

[redonninrf]

I forget what the base metal for that part of the engine is but stainless steel and aluminum do not mix. Even mixing SS with regular steel, or SS with SS, can seize. And when SS fasteners seize they seize. Trust me I know . One of the reasons I ended up owning a Dremel tool with cut-off wheels. If going with stainless use a generous amount of anti-seize compound.

Those 6mm screws are going to have a 1.0 mm pitch so you're looking for M6 x 1.0 - <length in mm> screws. True Value hardware stores carry the Servalite brand which usually turns out to be a really good selection of fasteners. Guess that's Hillman brand now since they bought Servalite. Anyways, usually a better selection than Lowes or Home Depot. The True Value store in my town even has chrome metric fasteners which would really raise the bling.

The black oxide socket head cap screws are cheaper and will look great at first but they rust easily. Strong screws but not the least bit rust-proof.

I'm very OCD about torqueing things. If the bike or car manual provides a torque setting I use it. For low-torque items like spark-plugs, brake bleed nipples, and cover screws I like the Craftsman inch-lb clicker torque wrench.

[Ram Jet]

Originally Posted by redonninrf

I forget what the base metal for that part of the engine is but stainless steel and aluminum do not mix. Even mixing SS with regular steel, or SS with SS, can seize. And when SS fasteners seize they seize. Trust me I know . One of the reasons I ended up owning a Dremel tool with cut-off wheels. If going with stainless use a generous amount of anti-seize compound.

Those 6mm screws are going to have a 1.0 mm pitch so you're looking for M6 x 1.0 - <length in mm> screws. True Value hardware stores carry the Servalite brand which usually turns out to be a really good selection of fasteners. Guess that's Hillman brand now since they bought Servalite. Anyways, usually a better selection than Lowes or Home Depot. The True Value store in my town even has chrome metric fasteners which would really raise the bling.

The black oxide socket head cap screws are cheaper and will look great at first but they rust easily. Strong screws but not the least bit rust-proof.

I'm very OCD about torqueing things. If the bike or car manual provides a torque setting I use it. For low-torque items like spark-plugs, brake bleed nipples, and cover screws I like the Craftsman inch-lb clicker torque wrench.

I have never had a stainless fastener lock-up in aluminum, cast iron or steel. I sure have had steel fasteners lock-up in aluminum and even wood in marine applications. Ask anyone who has disassembled an outboard boat motor. I always lubricate threads on anything I screw together. Maybe that's why. I would be extremely cautious using never/anti seize with a torque wrench. In fact, I will not do it. You need to reduce the torque value by about 50% if you do otherwise you will pull threads of twist-off screws/bolts.

Engine oil is a very good thread lubricant. Type "A" transmission fluid is OK also.

Bill

[jkv45]

Originally Posted by redonninrf

I forget what the base metal for that part of the engine is but stainless steel and aluminum do not mix. Even mixing SS with regular steel, or SS with SS, can seize. And when SS fasteners seize they seize. Trust me I know . One of the reasons I ended up owning a Dremel tool with cut-off wheels. If going with stainless use a generous amount of anti-seize compound.

Those 6mm screws are going to have a 1.0 mm pitch so you're looking for M6 x 1.0 - <length in mm> screws. True Value hardware stores carry the Servalite brand which usually turns out to be a really good selection of fasteners. Guess that's Hillman brand now since they bought Servalite. Anyways, usually a better selection than Lowes or Home Depot. The True Value store in my town even has chrome metric fasteners which would really raise the bling.

The black oxide socket head cap screws are cheaper and will look great at first but they rust easily. Strong screws but not the least bit rust-proof.

I'm very OCD about torqueing things. If the bike or car manual provides a torque setting I use it. For low-torque items like spark-plugs, brake bleed nipples, and cover screws I like the Craftsman inch-lb clicker torque wrench.

That is true for stainless fasteners, but it's also true for most any fastener going into aluminum.

I always use something on threads - anti-seize or medium threadlocker. I have has stainless bolts seize in aluminum (before I started using something on the threads), and they get really stuck.

As far as using a torque wrench on everything goes - be careful. Bolts like the OP was working with just don't need exact torque, and most of the time (especially with anything on the threads) you are going to over-do it, possibly breaking the bolt. Just use a 1/4" drive ratchet on the small stuff and make it "snug".

My son replaced a sprocket on his R6 recently, and torqued the bolts to the recommended spec. 3 out of 6 stripped. I told him I thought it was too much. He double checked. It was the proper amount. After reading some info on the R6 forums I found it wasn't uncommon at all. The published factory spec is too much for the size and grade of fastener. No idea why.

Sometimes you just need to trust your gut and not the specs.

[DannoXYZ]

Torque-spec may be off due to conversion from different measurement, some of metric ones perhaps.

Aluminium (6000) + carbon-steel bolts have 0.05v differential on galvanic series. Aluminium + stainless-steel bolts have 0.50v, so much more corrosive potential.

My friend who's mechanic @ Lucas Aviation in Santa Barbara tells me that no bolt ever goes into plane bare. It's either coated with lubricant or thread-locking compound. And torque used is logged in records.

[jkv45]

Originally Posted by JacRyann

Torque-spec may be off due to conversion from different measurement, some of metric ones perhaps.

Aluminium (6000) + carbon-steel bolts have 0.05v differential on galvanic series. Aluminium + stainless-steel bolts have 0.50v, so much more corrosive potential.

My friend who's mechanic @ Lucas Aviation in Santa Barbara tells me that no bolt ever goes into plane bare. It's either coated with lubricant or thread-locking compound. And torque used is logged in records.

In our case, the published spec was "correct" for that part - but over what you would expect for that fastener.

In the last few years I've started coating all fasteners with something as well.

Do they modify the torque spec based on using something on the threads, or is that factored in?

[Ram Jet]

Originally Posted by jkv45

In our case, the published spec was "correct" for that part - but over what you would expect for that fastener.

In the last few years I've started coating all fasteners with something as well.

Do they modify the torque spec based on using something on the threads, or is that factored in?

See Ghostt's previous post on this thread. Buy the way "lubed" does not mean anti seize compound I'm sure.

https://forum.ih8mud.com/threads/ant...-bolts.604971/

Bill

[Ralgha]

I've used a torque wrench on everything that the Ninja manual specifies torque for and never had a problem. Anyway, the OP's issue was not incorrect or improper use of a torque wrench, it was misreading the torque spec. The torque wrench was used properly, from what I read.

[tfkrocks]

You can also just go with no sprocket cover. One less thing to clean caked grime off of!

[Ram Jet]

Originally Posted by Ralgha

I've used a torque wrench on everything that the Ninja manual specifies torque for and never had a problem. Anyway, the OP's issue was not incorrect or improper use of a torque wrench, it was misreading the torque spec. The torque wrench was used properly, from what I read.

It's good you use a torque wrench. At least you won't strip out the threads on your oil sump drain plug like the previous orangutan owner of my bike did. Good God, you should have seen the rear axle adjusters on my bike. Tightened with a trip hammer. Both were replaced. Thank God he didn't do a valve adjustment.

Bill