Author Topic: swingarm sticking  (Read 5896 times)

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Offline Ryan6838

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Re: swingarm sticking
« Reply #25 on: April 18, 2010, 10:18:06 AM »
If gmonkeys like me he wants to do it himself. I know hondaman is the man but it not the same to pay to have stuff done. I doing my build to learn and have fun. we look to hondaman for his wealth of knowledge and experience.
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Offline MCRider

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Re: swingarm sticking
« Reply #26 on: April 18, 2010, 10:45:54 AM »
I think the thing to realize here is that if you want a result that is better than poor, this is not a DIY job. The best result that a DIY can achieve without machine tools is poor. Some experience would be helpful too, and this is not ajob we do regularly.

It took me a while to understand eactly how the swingarm pivot and bushings really worked. You can't get the aftermarket bushings back in without distorting them. Even then they won't lube properly.

I've done 2 myself and was amazed at what a poor job I'd done when finished. The dang thing still wouldn't move right. They both ultimately seized again. No matter what I did, they wouln't lube properly.

The last one HM did and it is smoooooth! And the lube goes in like it should.

Its nice to disassemble one and learn how it works. As far as a fine, worthwhile, long lasting rebuild, box it up to colorado and find something else to do.

Ride Safe:
Ron
1988 NT650 HawkGT;  1978 CB400 Hawk;  1975 CB750F -Free Bird; 1968 CB77 Super Hawk -Ticker;  Phaedrus 1972 CB750K2- Build Thread
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Offline gmonkey

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Re: swingarm sticking
« Reply #27 on: April 18, 2010, 11:59:15 AM »
If the collar is still flat and level, and not out of round more than 0.0008", it can be reused with good long-term results. I still modify them by adding grease grooves to them, like the earlier ones had, so grease will actually reach the bearing areas. Typical life on the OEM bushings on the 550 was about 8k-10k miles.

The collar looks fairly decent and the bike only has about 12k miles on it so I'm hoping it's not out of round but I did knacker it up pounding it out.  I'm adding pictures.  The ends are a bit belled out and have a groove around the bore where the socket sat that I used to pound it out.  The bell can probably be cut down but i'm afraid between this and the wear that was already on it, the collar is too short.  This look like a problem?

Also, where along the collar should I measure for diameter consistency?
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Offline MoTo-BunnY

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Re: swingarm sticking
« Reply #28 on: April 18, 2010, 04:48:00 PM »
I think the thing to realize here is that if you want a result that is better than poor, this is not a DIY job. The best result that a DIY can achieve without machine tools is poor. Some experience would be helpful too, and this is not ajob we do regularly.

It took me a while to understand eactly how the swingarm pivot and bushings really worked. You can't get the aftermarket bushings back in without distorting them. Even then they won't lube properly.

I've done 2 myself and was amazed at what a poor job I'd done when finished. The dang thing still wouldn't move right. They both ultimately seized again. No matter what I did, they wouln't lube properly.

The last one HM did and it is smoooooth! And the lube goes in like it should.

Its nice to disassemble one and learn how it works. As far as a fine, worthwhile, long lasting rebuild, box it up to colorado and find something else to do.



Thank you - very well put.

I'm all about DIY (do it yourself) on just about everything, even to a fault sometimes. It's just that this is something that requires the right tools and experience to do correctly and safely. This is definitely something you don't want to do wrong and half your swing arm suddenly seize up on you.


If gmonkeys like me he wants to do it himself. I know hondaman is the man but it not the same to pay to have stuff done. I doing my build to learn and have fun. we look to hondaman for his wealth of knowledge and experience.

Yeah, that's great, I know what you are saying and all but we are just trying to save a guy a LOT of hassle and potentially his butt, here. I have turned a wrench on dozens of different vehicles for many, many years. I have rebuilt engines, brakes, rewired electrical systems, welded and rebuilt rusty bodies, you name it, all by myself or with minimal instruction from someone else. However, even the most advanced mechanic knows there is always certain jobs when you call in a specialist to do something.   ;)
« Last Edit: April 18, 2010, 04:54:54 PM by MoTo-BunnY »
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Offline MCRider

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Re: swingarm sticking
« Reply #29 on: April 18, 2010, 04:56:03 PM »
I think the thing to realize here is that if you want a result that is better than poor, this is not a DIY job. The best result that a DIY can achieve without machine tools is poor. Some experience would be helpful too, and this is not ajob we do regularly.

It took me a while to understand eactly how the swingarm pivot and bushings really worked. You can't get the aftermarket bushings back in without distorting them. Even then they won't lube properly.

I've done 2 myself and was amazed at what a poor job I'd done when finished. The dang thing still wouldn't move right. They both ultimately seized again. No matter what I did, they wouln't lube properly.

The last one HM did and it is smoooooth! And the lube goes in like it should.

Its nice to disassemble one and learn how it works. As far as a fine, worthwhile, long lasting rebuild, box it up to colorado and find something else to do.



Thank you - very well put.

I'm all about DIY (do it yourself) on just about everything, even to a fault sometimes. It's just that this is something that requires the right tools and experience to do correctly and safely. This is definitely something you don't want to do wrong and half your swing arm suddenly seize up on you.
Well, thanks. But to be clear.
The seizing occurs over time, usually when its left to sit for a while. The suspension continues to work sort of, as the next most willing part will give. Like the bushings, seized to the collar, will instead rotate in the swingarm tube. Or the whole messs will scuff up and down at the points where the swingarm meets the frame. So its not a catastrophic failure. But a failure none the less which is irreversible short of an overhaul.

The swingarm with the weigth of a rider on it has a lot of leverage.

But the point stands its not an appropriate DIY job IMO, and I have done a couple. Without machine tools and a machinists skill, its just going to be poorly executed. And that's nothing against all of us DIY out there. Its just the design doesn't really lend itself to DIY.
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Offline gmonkey

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Re: swingarm sticking
« Reply #30 on: April 19, 2010, 03:49:30 PM »
Thank you all for your inputs.  Facts noted but I can't affor $200+shipping to have my swingarm rebuilt.  I don't doubt that it's worth the price but it's out of my budget.

The collar is bashed up.  As I see it, I have 3 options:
1.  Get the $30 brass aftermarket bushings, find a machine shop I have access to either at work or at school, check and ream those out after installing them if necessary and do my best to machine a new collar to match them.  What kind of steel can I use?
2.  Find a swingarm for sale with the pivot in decent shape.
3.  Part the bike out and save myself the frustration.

Actually, 4 options:
4.  Grind the bashed collar straight and stick it back in with the 1.9 bushings.  It's good enough for a test ride and who knows when this thing is going to be road-worthy anyway.
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Re: swingarm sticking
« Reply #31 on: April 19, 2010, 03:57:24 PM »
Thank you all for your inputs.  Facts noted but I can't affor $200+shipping to have my swingarm rebuilt.  I don't doubt that it's worth the price but it's out of my budget.

The collar is bashed up.  As I see it, I have 3 options:
1.  Get the $30 brass aftermarket bushings, find a machine shop I have access to either at work or at school, check and ream those out after installing them if necessary and do my best to machine a new collar to match them.  What kind of steel can I use?
2.  Find a swingarm for sale with the pivot in decent shape.
3.  Part the bike out and save myself the frustration.

Actually, 4 options:
4.  Grind the bashed collar straight and stick it back in with the 1.9 bushings.  It's good enough for a test ride and who knows when this thing is going to be road-worthy anyway.
Understandable: Been there too. The thing went down the road in a fashion with the pivot seized. So anything you do will be an improvement.
Ride Safe:
Ron
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Offline mystic_1

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Re: swingarm sticking
« Reply #32 on: April 20, 2010, 05:13:23 AM »
It might be cheapest and easiest to go with option #2 and get a replacement swingarm and collar that are in better condition.  That way, however you go about it at least you're starting with parts that are less damaged then the ones you have now.

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Offline HondaMan

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Re: swingarm sticking
« Reply #33 on: April 20, 2010, 06:28:51 AM »
You can still buy a collar that will fit: get the one from a CB750K2 if you're going to install the aftermarket bronze bearings. It will cost you about $45 plus shipping from KawasakiPartsNation.com or ServiceHonda.com online.

When you install those bronze bushings, heat the arm in an oven to at least 180 degrees and freeze the bushings, lube well: they will mushroom during installation and will require machining of some sort afterward to obtain enough clearance for the collar. Standard clearance is 0.0008" to 0.0012".

I get a lot of arms here where others have tried, only to have the bronze break or collapse during insertion. It's a bugger to get out afterward without damaging the arm further.  :o

If you have a lathe, you might try adjusting the new bushing's OD to be just 0.0005" bigger than the tube's ID, that will help. Some of those bushings I have seen are as much as 0.006" oversize, which makes them impossible to install without breaking something.

Good luck!  :)
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Offline Fritz

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Re: swingarm sticking
« Reply #34 on: April 20, 2010, 10:19:38 AM »
Hello Mark,

I'm planning to do my bushing in the near future. I have adjustable reamers here, so I will give it a try.

Just to get this straight:

Standard clearance is 0.0008" to 0.0012".

The Shop Manual says that the standard clearance is 0.1mm-0.3mm (0.004"-0.012"), "servicable limit: 0.5mm (0.02")"

Is there a typo in Honda's numbers or in yours, or are you just using smaller clearances because of the different material of your bushings?

Thanks,
Carsten
1976 CB550F

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Re: swingarm sticking
« Reply #35 on: April 20, 2010, 02:54:30 PM »
Hello Mark,

I'm planning to do my bushing in the near future. I have adjustable reamers here, so I will give it a try.

Just to get this straight:

Standard clearance is 0.0008" to 0.0012".

The Shop Manual says that the standard clearance is 0.1mm-0.3mm (0.004"-0.012"), "servicable limit: 0.5mm (0.02")"

Is there a typo in Honda's numbers or in yours, or are you just using smaller clearances because of the different material of your bushings?

Thanks,
Carsten

That's an interesting clearance number you've found: that would translate to about 0.4" of side-to-side motion at the rear axle!  :o
That would be downright dangerous. The original shop manual I have shows the numbers I use, with their wear limit being 0.012". This translates to about 0.240" at the rear axle, which is real uncomfortable at speeds above 40 MPH and in corners. The only Honda parts that actually achieved these numbers in production were in the original Zamac (hard plastic, like Bakelite) bushings that ended in 1971 when the phenolic ones appeared. The phenolic ones were actually 0.000" clearance, but are so spongy after they absorb grease that the rear wheel can still move sideways about 1/8" after about 5000 miles. They wear quickly, too.  :(
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

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Offline Fritz

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Re: swingarm sticking
« Reply #36 on: April 20, 2010, 03:51:49 PM »
Thanks Mark!

I've found the numbers in this file:
http://data.sohc4.net/SM500/HSM500550_10.pdf

Page 142 of the Shop Manual / page 8 of the PDF shows the numbers in the screen shot below.

Maybe I'm misreading them, but anyway: I've found so many typos in this manual that I will definitly trust your knowledge  ;D

Cheers
Carsten
1976 CB550F

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Re: swingarm sticking
« Reply #37 on: April 20, 2010, 04:02:02 PM »
Thanks Mark!

I've found the numbers in this file:
http://data.sohc4.net/SM500/HSM500550_10.pdf

Page 142 of the Shop Manual / page 8 of the PDF shows the numbers in the screen shot below.

Maybe I'm misreading them, but anyway: I've found so many typos in this manual that I will definitly trust your knowledge  ;D

Cheers
Carsten


There's definitely some kind of mistake, there. Those numbers don't even make sense amongst themselves.  :o  I mean, look at the min OD of the collar (0.843") and the max ID of the bushing (0.846") for starters: that's .003" minimum. Then the wear max comes out to 0.016", hokey smokes!
But, that's also not the first time I've seen that in Honda's manuals.  ???

To get the side-to-side looseness at the axle, take those numbers, multiply the clearance by 1.5 (presuming one side is only worn half as much as the other, here, for perspective), then multiply that number by the pivot-to-axle length of 18", and you'll see what I mean. Worst case, you would multiply the max wear number by 2x if both sides were equally worn, but the chain side always wears worse.

0.016" max wear * 1.5 * 18" = 0.432" side-to-side at the axle.

Honda generally set this upper limit to 0.240" (6mm) in years past on their smaller bikes, which is in keeping with a figure of about 0.008" max wear.
« Last Edit: April 20, 2010, 04:10:54 PM by HondaMan »
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The demons are repulsed when a man does good. Use that.
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Offline cookindaddy

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Re: swingarm sticking
« Reply #38 on: April 20, 2010, 05:00:16 PM »
Mine is a 78 and I am working on a 77 swing arm to replace the one I have. After reading this thread, I took to the swing arm with a socket, extension and a hammer as HM suggested and got the swing arm pivot tube out of the swing arm. It took a bit of persuading but no damage was done. Thanks Mark - I didn't realize that it was a separate part. It does not look too bad but both it and the bushings need some serious cleaning/burnishing. It definitely did not turn freely in the swing arm as it was suggested it should.
George with a black 78 CB750K (in Lion's Head, Ontario, Canada)

Offline MCRider

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Re: swingarm sticking
« Reply #39 on: April 20, 2010, 05:09:28 PM »
I would bet money that if I came across a CB that had been ridden any distance, then set aside, indoors or out, then pressed back into service that the swingarm pivot is seized.

It would maybe not be noticeable, as weight and leverage will force the swingarm up and down, but seized nevertheless.

One can never know what handling problems may be present, that ultimately reside at that pivot.

I'm happy to know that mine is no longer seized, that it has been resurrected to better than new state, and guaranteed for life. Thanks Mark!
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Offline gmonkey

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Re: swingarm sticking
« Reply #40 on: April 20, 2010, 08:10:54 PM »
You can still buy a collar that will fit: get the one from a CB750K2 if you're going to install the aftermarket bronze bearings. It will cost you about $45 plus shipping from KawasakiPartsNation.com or ServiceHonda.com online.

Do these earlier collars have the same OD and ID?  That is, can I use the top-hat bushings and the later model bolt that I have?
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Re: swingarm sticking
« Reply #41 on: April 20, 2010, 10:00:50 PM »
You can still buy a collar that will fit: get the one from a CB750K2 if you're going to install the aftermarket bronze bearings. It will cost you about $45 plus shipping from KawasakiPartsNation.com or ServiceHonda.com online.

Do these earlier collars have the same OD and ID?  That is, can I use the top-hat bushings and the later model bolt that I have?

If you mean the "later model collar"...
The later collars were about 0.002" larger OD on the outer half of the bearing areas and 0.0012" larger on the inner half of the bearing area, as compared to the earlier versions.

Early: bearings = 0.8422" nominal OD.
Late: Inner halves = 0.08438" OD. inner halves nominal, 0.8440" outer halves.

Most aftermarket flanged bronze bushings I have seen are 0.845" ID, so they start oversize: their OD is usually too big and they shrink during installation to be less than 0.8420" afterward. Some were as much as 0.005" OD oversize, impossible to install.
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

The demons are repulsed when a man does good. Use that.
Blood is thicker than water, but motor oil is thicker yet...so, don't mess with my SOHC4, or I might have to hurt you.
Hondaman's creed: "Bikers are family. Treat them accordingly."

Link to Hondaman Ignition: http://forums.sohc4.net/index.php?topic=67543.0

Link to My CB750 Book: https://www.lulu.com/search?adult_audience_rating=00&page=1&pageSize=10&q=my+cb750+book

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Offline 754

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Re: swingarm sticking
« Reply #42 on: April 20, 2010, 10:19:32 PM »
 If you get a stuck bushing that is not hardened.. cut threads into it with a tap, then insert a bol or fitting, then drive it out..
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Offline gmonkey

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Re: swingarm sticking
« Reply #43 on: April 21, 2010, 06:12:50 AM »
If you mean the "later model collar"...
The later collars were about 0.002" larger OD on the outer half of the bearing areas and 0.0012" larger on the inner half of the bearing area, as compared to the earlier versions.

Early: bearings = 0.8422" nominal OD.
Late: Inner halves = 0.08438" OD. inner halves nominal, 0.8440" outer halves.

Most aftermarket flanged bronze bushings I have seen are 0.845" ID, so they start oversize: their OD is usually too big and they shrink during installation to be less than 0.8420" afterward. Some were as much as 0.005" OD oversize, impossible to install.

I meant how are the two types of collar different so you answered my question.  I'm considering ordering or finding a used 750K2 collar and using it with the aftermarket flanged bushings.  Sounds like the flanged bushing ID will be pretty close to and slightly smaller than the K2 collar OD.

Will the later model's bolt work with the earlier model's collar?
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Offline cookindaddy

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Re: swingarm sticking
« Reply #44 on: April 21, 2010, 08:05:44 AM »
I just finished overhauling my 78K swing arm today. I drove out the pivot collar as suggested by Mark and I cleaned it up, as well as the bore and the ends of the axle in the swing arm. I am convinced that there are no bushings in my swing arm. The ends of the arm are steel and a very close fit to the steel pivot collar. So it is steel to steel with grease between. It was stuck solid of course with old grease and corrosion.

Anybody familar with the late models K7/K8 can comment on this arrangement and the apparent lack of bushing/collars?

I cleaned and lightly sanded the collar and the bore and now I am able to inject grease into the assy and it comes out the ends (it didn't before). The pivot tube now rotates smoothly and freely in the arm. I put the end caps on (there are also no "grease fiber/felt washers" as noted for the earlier ones). I then mounted it in the frame, tightened the bolt and the engine mounting bolts and the swing arm moves very nicely, smooth and there is no play at all. Very nice.
George with a black 78 CB750K (in Lion's Head, Ontario, Canada)

Offline Ryan6838

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Re: swingarm sticking
« Reply #45 on: April 21, 2010, 08:25:38 AM »
My 78k had the nylon bushings at the ends. Here's a few pics after I got them out my collar is trashed from what i can guess was most of its 34k miles was with it seized up. Id like to have hondaman do mine but I don't have 200 bucks or access to a machine shop so it looks like Ill have to go with an aftermarket kit till I have more money.
1978 cb750k

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Re: swingarm sticking
« Reply #46 on: April 21, 2010, 09:00:49 AM »
I just finished overhauling my 78K swing arm today. I drove out the pivot collar as suggested by Mark and I cleaned it up, as well as the bore and the ends of the axle in the swing arm. I am convinced that there are no bushings in my swing arm. The ends of the arm are steel and a very close fit to the steel pivot collar. So it is steel to steel with grease between. It was stuck solid of course with old grease and corrosion.

Anybody familar with the late models K7/K8 can comment on this arrangement and the apparent lack of bushing/collars?

I cleaned and lightly sanded the collar and the bore and now I am able to inject grease into the assy and it comes out the ends (it didn't before). The pivot tube now rotates smoothly and freely in the arm. I put the end caps on (there are also no "grease fiber/felt washers" as noted for the earlier ones). I then mounted it in the frame, tightened the bolt and the engine mounting bolts and the swing arm moves very nicely, smooth and there is no play at all. Very nice.
Here's a picture of the swingarm's parts. There are flanged phenolic bushings in the K5 through 78K arms. They often appear to not be there until you're familiar with the construction of it.  ;)

You cannot tell if there is slack in the pivot until you assemble the whole thing (unless you have bore gages). Then you must unload the pivot (like centerstand the bike, remove the shocks, let the wheel rest on the ground, or have someone hold the bike up on the wheels) and grab the rear wheel at the back of the tire with one hand, the frame with the other, and push and pull hard on the wheel sideways to see the play: do this at least 3 times before measuring the play, to displace the grease in the bearings first. Remember that for every 0.001" of play in the bearing, which you won't see manually, it is multiplied by 20 to 36 at the rear axle.

When you sanded that collar, you increased the clearance.  :(
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

The demons are repulsed when a man does good. Use that.
Blood is thicker than water, but motor oil is thicker yet...so, don't mess with my SOHC4, or I might have to hurt you.
Hondaman's creed: "Bikers are family. Treat them accordingly."

Link to Hondaman Ignition: http://forums.sohc4.net/index.php?topic=67543.0

Link to My CB750 Book: https://www.lulu.com/search?adult_audience_rating=00&page=1&pageSize=10&q=my+cb750+book

Link to website: www.SOHC4shop.com

Offline cookindaddy

  • I sure love this bike!
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Re: swingarm sticking
« Reply #47 on: April 21, 2010, 11:49:57 AM »
Thanks Mark. I studied your diagram and another and I see that the bushings are supposed to be there. I also know that I scratched the "bushing" on mine and it is steel and it seems one part with the swing arm. I have no explanation.

I also appreciate your advice on measuring clearance and your caution about sanding the parts. What I did was more like surface rust removal with very fine grit and several test fits to make sure that I only removed enough, but not too much.

With your help and advice (I love your book!), I am confident that I have a swing arm that will perform MUCH better than before since it was completely locked solid frozen tight before the rebuild and it wouldn't accept grease. Now it does!

Best regards,
George with a black 78 CB750K (in Lion's Head, Ontario, Canada)

Offline BobbyR

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Re: swingarm sticking
« Reply #48 on: April 21, 2010, 12:13:28 PM »
I have been led to believe that the grease fitting on my 78K is not a standard zerk fitting. Does anyone know if it is pressed in or threaded. It is not accepting grease. I have taps and zerks, I just want to be prepared if I go to change it. 
Dedicated to Sgt. Howard Bruckner 1950 - 1969. KIA LONG KHANH.

But we were boys, and boys will be boys, and so they will. To us, everything was dangerous, but what of that? Had we not been made to live forever?

Offline HondaMan

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Re: swingarm sticking
« Reply #49 on: April 21, 2010, 12:44:31 PM »
I have been led to believe that the grease fitting on my 78K is not a standard zerk fitting. Does anyone know if it is pressed in or threaded. It is not accepting grease. I have taps and zerks, I just want to be prepared if I go to change it. 
Most of the stock ones I've seen on those are a 45 degree North American zerk with 1/4-28 threads.  ;)
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

The demons are repulsed when a man does good. Use that.
Blood is thicker than water, but motor oil is thicker yet...so, don't mess with my SOHC4, or I might have to hurt you.
Hondaman's creed: "Bikers are family. Treat them accordingly."

Link to Hondaman Ignition: http://forums.sohc4.net/index.php?topic=67543.0

Link to My CB750 Book: https://www.lulu.com/search?adult_audience_rating=00&page=1&pageSize=10&q=my+cb750+book

Link to website: www.SOHC4shop.com