camshaft sprocket allen bolt: just how much @%$*ing torque did BMW put on this??

[Jerry_75_Guy]

My sad tale of cyl. head removal continues.

 

What is the best way to get this da#ned bolt off? I've tried using the appropriate sized hex head and a 1/2" ratchet, and a substantial rubber mallet to 'encourage' the bolt to loosen, but all this has done is to begin to round out the hex hole in the bolt.

 

An impact wrench was suggested, but beyond that, I've run out of Ideas and if the impact wrench merely manages to ruin the bolt further, then I'm really screwed.

 

I could really use a proper dealer network right now, but we all know how that's going.

[Ken H.]

Heat

[Stan Walker]

65 Nm

 

Stan

[Tony_K]

Yes heat. I was the culprit in getting it to that tight point it is also the reliever.

 

Depending on your skill level and access and knowledge of torches you may want to refer to others for this task.

[SWB]

Impact wrench is the only way to go with loosening a stuck, let alone aluminum bolt. It cycles with greater force and quickness than can be generated by hand alone, and more significantly, the force of the impact striking the wrench compresses the wrench against the bolt with more force than a person can generate. It's the ONLY tool I'll use on my dirt bikes, and I've never messed up a nut or bolt yet. I've also removed damaged bolts OTHER'S have screwed up (i.e. prior owners) with an impact wrench. If you haven't used one much, you'll be surprised how well it works.

 

And of course, as has already been mentioned, if the nut or bolt was locktited in, heat will be required, or you could shear the head of the bolt. I think you would probably be successful with a heat gun, an impact wrench, and patience.

[JB80120]

I believe that the "impact wrench" Scott is referring to is the manual type. You hold it in your hand and whack it with a hammer. If so, I agree it is a great tool for removing stuck bolts. I'm mentioning all this because if you use an air impact wrench, you will not get the benefits he mentions and are likely to bugger up the bolt in the effort. Just FYI.

[smiller]

Yes, heat, and lot's of it, in order to get the locking agent to release. Don't skip this because if you think you are in trouble now wait until you snap the head off of this bolt...

[Jerry_75_Guy]

Yes, heat, and lot's of it, in order to get the locking agent to release. Don't skip this because if you think you are in trouble now wait until you snap the head off of this bolt...

 

Yep!

Talk about cautious and concerned! After all that's transpired so far; I'm almost afraid to touch the bike

 

I bought a little hand torch from Sears, hopefully that will do the job.

 

Any suggestions on technique regarding the torch? Obviously wipe away the oil first ; I am concerned about how much is 'too much' heat since I'm aiming this at the bolt with the sprocket and chain still attached.

[smiller]

Personally I'm not fond of the idea of open flames around a motor vehicle and prefer electric heat guns. You can get an adequate but inexpensive one at Harbor Freight or Pep Boys (or nicer and pricier ones from many other sources) and when you're done fixing the bike (and that time will come, keep up the faith ) it's good for heat shrink tubing and a bunch of other uses as well. But a torch will work fine too if you've very careful.

 

Regarding the amount of heat, I don't think you have to worry too much about overheating these parts. The usual standard is when water sizzles a little when sprayed on the area.

[Jerry_75_Guy]

Thanks Seth. The water suggestion is a good one.

 

I'm starting to wonder if I should sacrifice a gerbil or something to the 'Motorcycle Maint. Gods' before I get started again

[Jerry_75_Guy]

Update:

 

Shoulda used the gerbil.

 

Lotsa heat, significant 'malleting' on impact driver: no movement of bolt.

 

It's time to call the cavalry, but I don't know of anyone in Indy who still works on BMW's.

 

I hear the new FJR's are nice

[No_Twilight]

Make sure the gerbil is a virgin.

 

I haven't looked at a manual or anything but one thing I would check is to make sure this isn't a left handed threaded bolt.

 

--Jerry

[smiller]

one thing I would check is to make sure this isn't a left handed threaded bolt.

Ya, good thought... do check that.

 

Do you have an air impact wrench? Lots of heat and repreated short bursts from an air impact wrench (at a low-ish torque setting since you're trying to 'shock' the threads loose rather than use brute force) should do it.

[mikefigielski]

The bolt is steel and there should be no locking agent on it, at least not from the factory. It is a standard thread also, not a left hand thread. I have always used a long 1/2 drive breaker bar with a good quality ( not rounded off) Allen socket and they have always come off, albeit with a sickening crack usually. We did have one that snapped off, but luckily we were changing cams anyway. Heat, Liquid Wrench, and a brand new quality Allen socket wih a long breaker bar might still do it if the head is not too rounded out. Hope this helps,

Mike

[SWB]

Lotsa heat, significant 'malleting' on impact driver: no movement of bolt.

 

1) You indicate that you're removing a bolt?? If you're removing a bolt, then I believe you'll need to heat the surrounding fitting (heat gun only, not a torch, and maybe then put ice on the bolt). Heating a bolt will expand it, and make it fit tighter. If you're removing a nut on a stud or bolt, then you use heat to both break the chemical seal (locktite) AND expand the nut. Least, I think that's how it's supposed to work.

 

2) Have you used a (manual, yes) impact driver wrench before? The only reason I asked this question is that there is a "wrong" way to use it. You need to ensure that you have the driver firmly in hand, and "snug it" counter-clockwise on the nut or bolt. (If you've got the rachet set backwards, i.e. clockwise, you'll find that out right away as soon as you attempt to snug the wrench against the nut.) Then use heavy, weighted plastic mallet for a careful, deliberate impact. The amount of movement resulting from the impact will be nearly imperceptible, but the nut WILL move. I've seen folks banging away (my son included, when he was about 8 yrs old working on his first bike) but not holding the wrench snug, and as soon as they snug the wrench, pop, it comes right off. Re-snug the wrench after every impact, and make each impact with the mallet hard and deliberate. You're not driving 4 inch spikes with a framing hammer; you're swinging like you would while hitting a rail road spike with a 20 lb sledge hammer. 3-4 impacts should be adequate. Any more than that and either you've rounded the hex bolt off, or it's not coming off.

 

Don't forget to use the old "penetrating" oil overnight trick.

 

Good luck. This can be a real frustrating job. If you can't get it off, any good repair shop (motorcycle or otherwise) should be able to do this for you, or "eazyout" or tap it out, if it comes to that.

[Jerry_75_Guy]

Thanks for the input Scott. Yep, sadly, I've tried all of these ideas with no luck so far, though it is pretty hard to heat the fixture without also heating the bolt, so that may be part of the problem; the cam sprocket is in the way.

 

I am suprised at how stubborn this particular bolt is. The bolt isn't rounded out yet, but it won't take too many more attempts before that happens, so I'm proceding with even more caution than I was before

[Wild Bill]

I agree with most of what has been said... I pulled my heads to dual plug them 15,000 miles and could not believe the force required to break that bolt loose! I ended up having some one just for safety to steady my bike on the center stand (just for piece of mind) and used a 1/2 inch 20 inch long breaker bar. Don't forget to have the fly wheel locking device in place.

 

These bolts were put in by big gorillas, you wll be surprize how tight they are...

 

Use some Grip Doctor (1 oz bottle from Sears) or some thing like it to help you grip the allen bolt, if you are starting to round it out...

 

Good Luck..

 

BK

[Wild Bill]

Jerry,

Well, were you able to get it done?

 

BK

[Jerry_75_Guy]

Thanks for checking in BK. I was going to wait and post a full report upon completion, but in short; yes.

 

I heated the bolt, then pounded it with the impact driver again and again, at least 8 or 10 cycles, with no result.

 

Then my friend brought over a 24" breaker bar, and we slid a 36" length of pipe onto the end of that, and I torqued the bolt as he struck it with a 3lb hammer. With not so much as a creak, it slowly, and easily rotated free. It was very anticlimactic given the torture it had put me through up to that point. I thought sure it would shear off.

 

I've since had my Indy car machinist buddy bore out the offending material, and as soon as the new bolt I ordered comes in (the old one is still serviceable, but it's starting to get a bit rounded out, and felt it was time to replace it) I'll install the timesert and reassemble everything.

 

Unfortunately, by the time that is done, 600mi are put on the bike (even if I do it in a day or two), retorque the head attach bolts, and change the tires, we'll have lost our window to go to the rally in VT, which I'd been planning on for months. Very depressing, as this is probably my last chance for a longish (7days) trip before I go back to school in Aug.

[Stan Walker]

Unfortunately, by the time that is done, 600mi are put on the bike (even if I do it in a day or two), retorque the head attach bolts, and change the tires,

 

Change the tires now, take the trip and just be gentle on the engine. Retorque after the trip. 600 miles isn't an absolute number, but a minimum to give the gasket time to compress.

 

Or take the torque wrench with you, spend a couple of hours in a parking lot and just do it after 600 miles.

 

Stan

[Wild Bill]

I say go for it too... Re touque ing is an easy thing to do... Many at the rally will have the knowledge and be glad to help!!

 

BK

[Jerry_75_Guy]

Change the tires now, take the trip and just be gentle on the engine. Retorque after the trip. 600 miles isn't an absolute number, but a minimum to give the gasket time to compress.

 

Or take the torque wrench with you, spend a couple of hours in a parking lot and just do it after 600 miles.

 

Stan

 

It's a good suggestion, in fact I started to get that "why didn't I think of that!??" feeling for a few seconds, but then remembered my friend ordered the bolt 'late' ( he was out sick with the 24hr flu on order day and it didn't get it called in until fri.) and he claimed it wouldn't be in until middle to end of this coming week (he wanted to order it through work to save me a few $$ and shipping), and, of course, the rally starts this thurs. and ends sun., and with my wife on the back it's a two day ride from Indy to VT (she'll tolerate ~500mi/day, but not the 900+ I'd be willing to ride to make it in a day), so I'm pretty sure I hear the fat lady singin' on this one; just ran out of time, I'm afraid.

 

It did occur to me to take the VFR, but then I'd be solo, and having my wife there to share the experience with is more than half the fun, and the 'Contiforce' tires it came with are worn enough that I seriously doubt they'd make it another 1800mi, plus day trips during the rally. Of course, tire changes at the rally are always a possibility, but as close as I am to the wear bars on the back, I'm not sure (given that this is my first exposure to this make and model of tire) if it would even make it all the way to VT without need of a change (they sure started to square off fast during my last southern Indiana day trip [yes, they were inflated properly]).

 

Everyway I turn, it looks like maybe not 'checkmate', but at least 'check'.

 

(the silver lining is that I'm already considering that the $$ saved from not going on the rally trip can now be rationalized into farkles for the VFR like an Autocom to pipe the V1 through, and the associated mount for the V1 or some HelenTwoWheels bags to attach to the top of the RT's sidecases, or both! )