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TECHNICAL MOTOBRICK WRENCHING In Remembrance of Inge K. => The Motobrick Workshop => Topic started by: whosyurdaddy on May 12, 2017, 04:50:48 PM
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While doing my spline service I thought I would source new clutch bolts other than BMW . A local nut and bolt shop actually had 7mm bolts but with a hex head , I went ahead and bought from BMW but when comparing the hex head versus socket head I'm really not sure why the hex can't be used . I'm just wondering if anyone has gone the hex head route and did it work .
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I'm not a metallurgist or a fastener engineer but I think the clutch bolts aren't special because of the fastener type but rather because of the head profile and type of metal. The bolts are designed to work with the teeth washers so that the teeth washers grip into the metal. These bolts strip out really easily, which indicates to me that the metal is soft rather than super hard and/or the socket is too shallow to accommodate the amount of torque put on them -- but I think it's the former. I think the soft metal of the bolt and the teeth washers are paired and the low head is used maybe because has a wider profile than a standard socket or hex head.
I would definitely not use any bolt without the teeth washer that goes under it according to the manuals and the fiche, and if the metal of the bolt is too hard for the teeth washer to grip into, it's just going to flatten the teeth washer when you torque it down and that will defeat the whole purpose of the teeth washer.
I don't know what will 'work' and what won't - but I'd think you'd want to make sure that whatever bolt you use has the same height as the low head bolt it is replacing. For myself, I'd rather use a used clutch bolt than a new one that wasn't a match with the OEM one.
I was looking here for aftermarket options:
http://www.mrmetric.com/product/metric-socket-screws/metric-low-head-screws?page=2 (http://www.mrmetric.com/product/metric-socket-screws/metric-low-head-screws?page=2)
Have it on my list to do to call them and possible even send them a used clutch bolt to compare but I can't find the big bag of old clutch bolts I had somewhere -- losing shit is the bane of my existence.
Sorry I can't give you a more comprehensive answer. The other place low head bolts are used on the K75 is to keep the footpeg assembly together from the inside of the footpeg mount. If those are the same kind of metal, then maybe it's safe to say that the clutch bolt isn't any softer than any other low head bolt you can find.
THere are a number of clutch bolt threads here -- search for 'clutch bolt' -- maybe you'll turn up more info.
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The original washer are called gripper washer I believe but when you order from BMW now you get shaker washers which I have a drawer full , very common at most hardware stores . The bolts themselves from what I was told are a soft alloy . I'm finding nothing special about the bolts other than I don't want to tear my bike apart again because I tried to be different
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If your worried about the bolts loosening you could apply medium strength Loctite as an extra precaution.
Regards Martin.
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If your worried about the bolts loosening you could apply medium strength Loctite as an extra precaution.
Regards Martin.
Hmmm...have you ever done that with non OEM clutch bolts, Martin? Trying to get poor whosyurdaddy to be the guinea pig, are you? :yow
The original washer are called gripper washer I believe but when you order from BMW now you get shaker washers which I have a drawer full , very common at most hardware stores . The bolts themselves from what I was told are a soft alloy . I'm finding nothing special about the bolts other than I don't want to tear my bike apart again because I tried to be different
Actually, according to my research they're called external tooth washers, also serrated lock washers:
https://www.grainger.com/product/GRAINGER-APPROVED-Steel-External-Tooth-WP136278/_/N-1z0o4o3/Ntt-External+Tooth%2C+Closed+Perimeter?sst=subset&s_pp=false&picUrl=//static.grainger.com/rp/s/is/image/Grainger/25DN34_AS01? (https://www.grainger.com/product/GRAINGER-APPROVED-Steel-External-Tooth-WP136278/_/N-1z0o4o3/Ntt-External+Tooth%2C+Closed+Perimeter?sst=subset&s_pp=false&picUrl=//static.grainger.com/rp/s/is/image/Grainger/25DN34_AS01?)$smthumb$
http://www.mrmetric.com/M61165 (http://www.mrmetric.com/M61165)
and if BMW is selling your basic Ace Hardware variety for $1.95 a pop, then that is really fuuuuuuud up, because the ones I found at my local Ace weren't even close.
Here's what the OEM part is supposed to look like according to the Max BMW fiche...see attachment.
Truth is, I don't know why they designed it why they did, but I want to stick to the original spec and find the closest aftermarket option there is...but that's just me.
whosyurdaddy, if it were me I'd use whatever used OEM bolts I have and whatever washers BMW gave you and button 'er up. If you don't have a complete set of used OEM clutch bolts at hand, I'd order new OEM ones to complete the set with one or two to spare. I personally wouldn't use any metric bolt that wasn't low head and at least a close match to the OEM. But like I said, I'm not a metallurgist, just some dude with a couple K75s and a wrench who has to believe that the BMW engineers back in 1982 had a reason for the decisions they made. Hopefully by the next time around around someone will have figured out what the aftermarket offering is, because the prices BMW is charging for the ten-cent bolts is...well, let's call it non-consensual anal penetration by a foreign object.
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Motohobo actually yes, I reused the bolts and washers and a dab of Loctite. I would rather use the original unless you can get a really close match. But in saying that if a bolt is the same, except that it is a hex instead of an allen and the head has clearance and the washers are correct for the bolt and the application, I can't really see it causing any problems. :dunno
Regards Martin.
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Motohobo actually yes, I reused the bolts and washers and a dab of Loctite. I would rather use the original unless you can get a really close match. But in saying that if a bolt is the same, except that it is a hex instead of an allen and the head has clearance and the washers are correct for the bolt and the application, I can't really see it causing any problems. :dunno
Regards Martin.
Well -- hats off to you! I don't have to guts to stray too far from 'the book' -- you're an inspiration to us all :clap:
I assume you're talking about blue Loctite -- the kind that can be removed with hand tools.
There you go, whosurdaddy, if it's good enough for Martin it should be good enough for you.
I'm still going to look for a match for those OEM parts, though. I've stripped enough of those clutch bolts even without Loctite -- would prefer no additional complications in the process. But that's just me :-)
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I'm not worried about bolts backing out I was just looking for a more cost effective replacement part . I mean $38 and change for 6 bolts and washers . I am using the BMW bolts because the damage that could happen is not worth the risk and someone mentioned the weight difference between the 2 bolts might cause a problem .
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I'm not worried about bolts backing out I was just looking for a more cost effective replacement part . I mean $38 and change for 6 bolts and washers . I am using the BMW bolts because the damage that could happen is not worth the risk and someone mentioned the weight difference between the 2 bolts might cause a problem .
That's a really good point -- hadn't thought of that.
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I am using the BMW bolts because the damage that could happen is not worth the risk and someone mentioned the weight difference between the 2 bolts might cause a problem .
It's time for you to consider polling the membership, hoosierdaddy. I've rough draft here of poll questions that you can use gratis, based on your apparent rejection of non-oem solutions to this first-world dilemma.
1. Assemble with oem old bolts and oem old washers.
2. Assemble with oem old bolts and oem new washers.
3. Assemble with oem new bolts and oem old washers.
4. Assemble with oem new bolts and oem new washers.
5. Wait for for that certain, trusty someone to tell you what you should do.
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I've stripped enough of those clutch bolts even without Loctite -- would prefer no additional complications in the process. But that's just me :-)
Heat, from a high-wattage soldering iron or a small torch, will help break the bond of blue or red Loctite. Helps a lot with non-Loctited bolts, too.
Andy
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Heat, from a high-wattage soldering iron or a small torch, will help break the bond of blue or red Loctite. Helps a lot with non-Loctited bolts, too.
Andy
Sure, but it's more an issue of how many hoops do I want to jump through? I want to put a washer down, put a bolt over it and torque it down, repeat 5 times. I don't want to be putting 6X loctite on there when that's not necessary if you have the correct parts. That's not a piece that should require any heat. I've drilled out maybe 2% of those bolts...much less than the time required to apply loctite and remove its residue 6X per cycle.
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Sure, but it's more an issue of how many hoops do I want to jump through? I want to put a washer down, put a bolt over it and torque it down, repeat 5 times. I don't want to be putting 6X loctite on there when that's not necessary if you have the correct parts. That's not a piece that should require any heat. I've drilled out maybe 2% of those bolts...much less than the time required to apply loctite and remove its residue 6X per cycle.
That's fine... I was just putting the technique out there. It's saved me a lot of time over the years.
Andy
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Well -- just got an answer from the Flying Brickers across the sea -- AFAIC this problem is solved.
That's about $16 for the set...can't beat that with a baseball bat.
http://www.jt-c.com/product_info.php?info=p282_schraubensatz-bmw-21211454417---21211242377.html (http://www.jt-c.com/product_info.php?info=p282_schraubensatz-bmw-21211454417---21211242377.html)
I am placing an order very soon -- PM me if you want some....save on intl shipping.
V
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Wow, what a great site!
Did you ever want to connect something to the accessory plug in the relay box??? They have the mating connector with 4 ft of wire connected to it for under $20. Could have used it last week when I started wiring a cruise on my RT.
http://www.jt-c.com/product_info.php?info=p74_the-k-cable.html
They're in my bookmarks. Thanks for the heads up Motorhobo!
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Yeah -- this Till guy's store is like a candy shop for motobrickers.
BTW the answer I got to the reusability question was basically -- if you can get it out in one piece, reuse it. He was referring to the bolts though, not the tooth washers. Those flatten out and lose their bite after one use, so I'm going to look for a supplier -- might not be so easy since these are M7 bolts -- not a very common size.
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Motohobo we have a bigger problem than inmates in the US and the UK. Local availability and the price of OEM parts which can be four times plus your price. Any thing remotely unusual is extremely hard to get, and if you do find it it will at least cost you a leg, if not an arm as well. We have one BMW wrecker in Queensland and he can charge what ever he likes. However I do love a challenge. and it keeps me on my toes finding ways to get around non availability and exorbitant prices.
Regards Martin.
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Hey Martin -- well, I guess point from this thread...
http://www.motobrick.com/index.php/topic,9681.25.html (http://www.motobrick.com/index.php/topic,9681.25.html)
Is that BMW OEM per se is dead as a doornail -- which is where BMW is pushing it. The aftermarket BMW suppliers ship to OZ, don't they? Check out the shipping options link on the Till's site:
http://www.jt-c.com/ (http://www.jt-c.com/)
OZ isn't listed but I think that's an oversight rather than an exclusion -- they ship everywhere else for $15 US. BMW doesn't want your business -- they've been working with people like Till to behind the scenes to offload the supply chain to third party vendors. We're in the same boat as you in that there are no more brick--and-mortar stores to buy things from. We have to order them and wait -- you have to wait longer of course -- but the price is going to be the same worldwide plus shipping.
I think what we motobrickers need to do is to find out what the third party vendors have and organize collective buying orders. There's a whole section on the flyingbrick.de site for collective orders. We need to buy in advance instead of on demand and forget about BMW dealers as suppliers of what we need. Nobody is going to buy an exhaust or heat shield or transmission new -- we're going to get that from scrap. All the rest we get from the third party folks per UPS.
That there's only one breaker in OZ -- that's a bummer -- seems like every OZ motobricker needs at least one parts bike on the premises...
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It's time for you to consider polling the membership, hoosierdaddy. I've rough draft here of poll questions that you can use gratis, based on your apparent rejection of non-oem solutions to this first-world dilemma.
1. Assemble with oem old bolts and oem old washers.
2. Assemble with oem old bolts and oem new washers.
3. Assemble with oem new bolts and oem old washers.
4. Assemble with oem new bolts and oem new washers.
5. Wait for for that certain, trusty someone to tell you what you should do.
Thats a good start although number 3 is irrelevant since the original oem washers are not removable . I have a revised version I think is closer to what this post is about .
1. Who is OK with spending nearly $40 for 6 bolts and washers
2. Who is NOT OK with spending nearly $40 for 6 bolts and washers
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One wrecker in Queensland he is local but knows how to charge a captive audience, two engine mounting bolts crash bar type $20.00 exhaust mica gasket $50.00 speedo housing just the shell $100.00. I don't know entirely what the other states have as far as BMW wreckers some probably better some worse. For the last couple of years I have been trying to slowly buy parts that will disappear or that take too much time to get overseas. I also trying to find old specialist tradesman who are now disappearing I have found a good source of brake hoses a master cylinder sleeve guy. And I might have found a guy the does splines, I am still trying for more information. I now have a lot of bits now in stock, but I do need a few more expensive things like a gearbox and drive shaft. I do have a mate with three K75's and a K100 and another pile of K75 bits two engines boxes and shafts. I was trying to help him get them back on the road but have given up. He won't sell anything to anybody but he has given me a couple of things and I can borrow bits while I am chasing parts. I have made a lot of special tools required for the brick and I have a pretty good workshop. I love the challenge of keeping my brick going without having to sacrifice an arm or a leg. :hehehe I would however love access to your Harbour Freight and some of your other suppliers, some of which won't ship to OZ.
Regards a vented Martin. :riding:
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Martin, are you a member at the K100 forum?
http://www.k100-forum.com/portal
There is a very large, organized and active contingent of Ozzies there. They swap parts, work on each other's bikes, and seem to always have a ride organized to go somewhere.
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I used to be, I tried to get back on but I had trouble with Email addresses matching with user name. User name used, Email address used, could not work out what matched what. I actually tried to find Motobrickers locally with one post but alas forsooth it was in vane. I am resigned to Bricking alone. :dunno However I might try again now that I have a new Email provider. :hehehe
Regards Martin.
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1. Who is OK with spending nearly $40 for 6 bolts and washers
2. Who is NOT OK with spending nearly $40 for 6 bolts and washers
Doesn't bother me. I like supporting local business and I like M&Ms. :hehehe
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Doesn't bother me. I like supporting local business and I like M&Ms. :hehehe
Of course, I reused mine after I measured the friction disc last time I did a spline lube and I've ridden 22K miles since then, so my vote will skew your data. :giggles
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Thats a good start although number 3 is irrelevant since the original oem washers are not removable .
Why do you suppose they are listed separately in the parts fiche? Am I involved with the wrong bolts and washers here? Help me catch up.

Washer and screw from MAX BMW parts fiche.png (17.29 kB . 163x258 - viewed 451 times)
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Why do you suppose they are listed separately in the parts fiche? Am I involved with the wrong bolts and washers here? Help me catch up.
No Laitch, you are correct -- but those washers bite in to the soft alloy of the original OEM bolt and maybe whosurdaddy thought they were one part -- they're not. Hence my argument that the original washers were specially mated to that specialty bolt that originally was made of some specially engineered alloy for some special reason devised by some special people who are long since dead and can no longer specify the special reason so everybody said feck it and found some bolts that look like that and that's gonna have to be good 'nuff for the aftermarket -- and that's good 'nuff for me.
I don't have a problem with $18 plus tax and shipping for a handful of bolts and washers to support my local dealer -- but $38? That's where I conclude the dealer doesn't want my business.
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I realize the bolts and washers are 2 different parts , I'm just saying my original bolts and washer will not separate so there is no chance to reuse oem old washers with oem new bolts . Motorhobo looks like you've found a less expensive source for the bolts if the shipping isn't too high . I just think here in the states that someone sells a comparable bolt to the original at a lesser cost . The hex head bolts I found I think would work just fine but do I have the guts to try them "no" so thats why I'm staying with oem and complaining about the high cost . I will gladly send 6 - 7m hex head bolts free to anyone that would like to give them a try .
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Well it might be time to admit that BMW may not be so bad after all . I just looked in McMaster-Carr's catalog and for a 7m socket head black oxide screw and they cost $3.91 up to $5.31 each depending on the length and I honestly haven't measured the length of a clutch bolt .
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If people want to think it's their attraction as objects of sodomy that is causing the rise in prices for their elderly bikes' parts instead of the effects of supply, demand and labor, I will defend their right to that belief—not to death maybe, but that would depend on my mood. :giggles
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Well it might be time to admit that BMW may not be so bad after all . I just looked in McMaster-Carr's catalog and for a 7m socket head black oxide screw and they cost $3.91 up to $5.31 each depending on the length and I honestly haven't measured the length of a clutch bolt .
You can probably source them cheaper than McMaster Carr but I think the complete pack from Till in DE is the way to go -- shipping from EU is $15 -- Bob's BMW charges $9 which is highway robbery IMO. So ordering from Till will cost 6 bucks more (or maybe less, since he's not charging sales tax on international -- no idea whether there's customs fees) and take at least a week longer than a domestic order. That only makes sense if there's more than a handful of fasteners in the package.
I'm going to order some stuff from him soon -- I'll start a thread about a collective order when I'm ready and anyone wants to do so can join in. It will be soon, but not sure when -- depends on how my bike runs when I get it down from the lift which hopefully will be today.