1988(LT) Engine-to-frame bolts

naddy100 · 11-06-2009, 06:57 PM

On a 1988 K100(LT), how do I get the correct torque on the right front bolt that holds the engine to the frame?

I had the interesting experience of pulling into my parking spot at work the other day and seeing radiator fluid in a pool under the bike. The problem was that the right front bolt holding the engine to the frame had come out. The engine had dropped a few inches and pulled loose from the radiator hoses. The radiator hoses aren't the issue at the moment. The bolt is.

I have a 1987 parts bike on my back porch. Okay, I really intend to get the 87 running again, but in the meantime I keep pirating parts from it so that the 88 stays on the road. I just pulled the right front bolt out of it. The odds of the 87 ever running again get slimmer all the time.

In Clymers, the left front bolt looks like it has a nut on the other side. My issue is the right front. The right front runs through the frame and then tightens into the engine block on the other side.

The bolt's exterior head has a nice hand grabby texture. It's not at all clear what I'm supposed to use to torque it to it's 28-32 ft lbs (or whatever). It's not an allen bolt. It's not a hex-sided bolt. How do I torque it?

I'll find out whether the interior threads on the engine block are stripped when I try to put it in, but that's another bridge. Right now, let's talk about the bolt.

Noel

98lee · 11-06-2009, 07:59 PM

Should be a 10mm x 60mm allen head bolt, not a "hand grabby" bolt.

Maybe someone replaced that bolt on your parts bike with the wrong bolt.

naddy100 · 11-06-2009, 08:14 PM

Quote:

Originally Posted by 98lee

Should be a 10mm x 60mm allen head bolt

Thanks. Clymers describes it as an allen head bolt. Hmm.

Incidentally, the center of the bolt head -- like where the allen wrench would go -- is a threaded hole as though some cylinder guards or something might bolt on.

Noel.

lostboy · 11-06-2009, 09:46 PM

The "grabby" bolt is indeed for a crash guard. You can remove or retorque it with a 12 point socket. Finding a 12-point metric socket in that size can be difficult, but there is an english ("American") size that fits well enough to do the job.

58058 · 11-07-2009, 10:17 AM

Just a heads-up that may mean nothing on yours....mine on my K12RS disappeared a while after some dealer service. When I purchased the bolt called for in the manual from the dealer, it was to short, by 10mm? The end was just touching the threads in the engine case, got the correct one from a local specialty bolt supplier, same for the shifter attacheming fillister bolt. It took a little playing (with a jack I believe) to ensure that things lined up correctly to avoid cross threading. I simply torqued with my allen wrench socket as normal.

naddy100 · 11-07-2009, 10:58 AM

I appreciate the continued comments. It helps to hear thinking that's independent of me.

Some facts in the light of day. The right front bolt broke off in the engine case. The left front bolt is missing. [edit: the left bolt threads to the engine case, like 98lee states below. ]

To torque the 'official' bolts, I'm thinking about putting a small hex-head bolt in the threaded hole in the head of the 'official' bolt. That second smaller bolt would be something that a regular socket would fit. I'm sure that this isn't exact because I'll be torquing two sets of threads rather than one. There's a 4 ft lb latitude in the torque value, so I hope I'm not too far off.

Noel

98lee · 11-07-2009, 11:39 AM

The "official" bolts are allen head.

Your "grabby head" bolts with the internal thread are for the optional crash bars that evidently you do not have.

Why not just replace them with the correct bolts? Allen head 10mm x 60mm for the right side and 10mm x 90mm with nut and washer on the left side. A lot of good hardware stores will carry them, but they will probably be black instead of the factory silver. Dealers will probably stock them.
01 07119901107 FILLISTER-HEAD SCREW (M10X60) 0.10 1 $2.08
02 07119901110 FILLISTER-HEAD SCREW (M10X90) 0.14 1 $2.16

naddy100 · 11-08-2009, 10:23 PM

Thanks for the help.

I was driving around town today (Sunday) with my wife. I was collecting tools and hardware to tackle the bolt that had broken off in the engine case. Wait -- who was that at the gas station? How many side cars can there be in a tiny town like this? That's gotta be Vech! Dang! How long does it take for a left turn signal to let me through? I need to talk to Vech!

So, we got back to the station before he left. I wish I'd had a camera with me. Vech (BenchMark Works http://www.benchmarkworks.com/) has a newly put-together side car. It's bright blue, with big driving lights, slick internal wiring, comm system, gps, and some incredible bronze-looking sculptured cylinder head covers. Nice as can be. I don't remember all the technical stuff about the bike, but it's seriously cool.

I guess the important thing here is that he invited me back to the shop, checked my parts-bike bolt threads against his dies and gave me a crash course in removing broken bolts. Incidentally, my 'hand grabby' bolt head turns out to take a 22mm 12point socket. The socket would probably fit better if I had not used pliers to remove the bolts from the old bike.

This afternoon was anticlimactic. When I got home I prepared to lay siege to the broken bolt but it popped out as soon as I put a drill bit to it. Kinda disappointing. I was prepared for a much bigger battle.

I've still gotta line up the frame and engine holes and torque things down, but I'm in better shape than I was last night.

Noel

11-06-2009, 06:57 PM	#1
naddy100 Registered User Join Date: Jul 2003 Location: Starkville, Mississippi Posts: 271	1988(LT) Engine-to-frame bolts On a 1988 K100(LT), how do I get the correct torque on the right front bolt that holds the engine to the frame? I had the interesting experience of pulling into my parking spot at work the other day and seeing radiator fluid in a pool under the bike. The problem was that the right front bolt holding the engine to the frame had come out. The engine had dropped a few inches and pulled loose from the radiator hoses. The radiator hoses aren't the issue at the moment. The bolt is. I have a 1987 parts bike on my back porch. Okay, I really intend to get the 87 running again, but in the meantime I keep pirating parts from it so that the 88 stays on the road. I just pulled the right front bolt out of it. The odds of the 87 ever running again get slimmer all the time. In Clymers, the left front bolt looks like it has a nut on the other side. My issue is the right front. The right front runs through the frame and then tightens into the engine block on the other side. The bolt's exterior head has a nice hand grabby texture. It's not at all clear what I'm supposed to use to torque it to it's 28-32 ft lbs (or whatever). It's not an allen bolt. It's not a hex-sided bolt. How do I torque it? I'll find out whether the interior threads on the engine block are stripped when I try to put it in, but that's another bridge. Right now, let's talk about the bolt. Noel

11-06-2009, 07:59 PM	#2
98lee 3 Red Bricks Join Date: Jan 2007 Location: Pleasanton, Ca. Posts: 959	Should be a 10mm x 60mm allen head bolt, not a "hand grabby" bolt. Maybe someone replaced that bolt on your parts bike with the wrong bolt. __________________ LONG MAY YOUR BRICK FLY! Ride Safe, Ride Far, Ride Often Lee Fulton 3 Marakesh Red K75Ss Mine, Hers, Spare

11-07-2009, 10:17 AM	#5
58058 Registered User Join Date: Jun 2007 Location: Mendocino, California Posts: 224	Just a heads-up that may mean nothing on yours....mine on my K12RS disappeared a while after some dealer service. When I purchased the bolt called for in the manual from the dealer, it was to short, by 10mm? The end was just touching the threads in the engine case, got the correct one from a local specialty bolt supplier, same for the shifter attacheming fillister bolt. It took a little playing (with a jack I believe) to ensure that things lined up correctly to avoid cross threading. I simply torqued with my allen wrench socket as normal. __________________ Jim Douglas '09 K1300S @ >1000mi, '00 K1200RS current @124K, '93 K1100RS traded @78K, '85 K100RS sold @44K, http://www.seagullbb.com/

11-07-2009, 10:58 AM	#6
naddy100 Registered User Join Date: Jul 2003 Location: Starkville, Mississippi Posts: 271	I appreciate the continued comments. It helps to hear thinking that's independent of me. Some facts in the light of day. The right front bolt broke off in the engine case. The left front bolt is missing. [edit: the left bolt threads to the engine case, like 98lee states below. ] To torque the 'official' bolts, I'm thinking about putting a small hex-head bolt in the threaded hole in the head of the 'official' bolt. That second smaller bolt would be something that a regular socket would fit. I'm sure that this isn't exact because I'll be torquing two sets of threads rather than one. There's a 4 ft lb latitude in the torque value, so I hope I'm not too far off. Noel Last edited by naddy100; 11-08-2009 at 05:44 PM.

11-07-2009, 11:39 AM	#7
98lee 3 Red Bricks Join Date: Jan 2007 Location: Pleasanton, Ca. Posts: 959	The "official" bolts are allen head. Your "grabby head" bolts with the internal thread are for the optional crash bars that evidently you do not have. Why not just replace them with the correct bolts? Allen head 10mm x 60mm for the right side and 10mm x 90mm with nut and washer on the left side. A lot of good hardware stores will carry them, but they will probably be black instead of the factory silver. Dealers will probably stock them. 01 07119901107 FILLISTER-HEAD SCREW (M10X60) 0.10 1 $2.08 02 07119901110 FILLISTER-HEAD SCREW (M10X90) 0.14 1 $2.16 __________________ LONG MAY YOUR BRICK FLY! Ride Safe, Ride Far, Ride Often Lee Fulton 3 Marakesh Red K75Ss Mine, Hers, Spare

11-06-2009, 09:46 PM	#4
lostboy Registered User Join Date: Sep 2007 Posts: 664	The "grabby" bolt is indeed for a crash guard. You can remove or retorque it with a 12 point socket. Finding a 12-point metric socket in that size can be difficult, but there is an english ("American") size that fits well enough to do the job.

11-08-2009, 10:23 PM	#8
naddy100 Registered User Join Date: Jul 2003 Location: Starkville, Mississippi Posts: 271	Thanks for the help. I was driving around town today (Sunday) with my wife. I was collecting tools and hardware to tackle the bolt that had broken off in the engine case. Wait -- who was that at the gas station? How many side cars can there be in a tiny town like this? That's gotta be Vech! Dang! How long does it take for a left turn signal to let me through? I need to talk to Vech! So, we got back to the station before he left. I wish I'd had a camera with me. Vech (BenchMark Works http://www.benchmarkworks.com/) has a newly put-together side car. It's bright blue, with big driving lights, slick internal wiring, comm system, gps, and some incredible bronze-looking sculptured cylinder head covers. Nice as can be. I don't remember all the technical stuff about the bike, but it's seriously cool. I guess the important thing here is that he invited me back to the shop, checked my parts-bike bolt threads against his dies and gave me a crash course in removing broken bolts. Incidentally, my 'hand grabby' bolt head turns out to take a 22mm 12point socket. The socket would probably fit better if I had not used pliers to remove the bolts from the old bike. This afternoon was anticlimactic. When I got home I prepared to lay siege to the broken bolt but it popped out as soon as I put a drill bit to it. Kinda disappointing. I was prepared for a much bigger battle. I've still gotta line up the frame and engine holes and torque things down, but I'm in better shape than I was last night. Noel