Author Topic: 78 CB 550K motor rebuild  (Read 64183 times)

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Offline AlekStooge

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Re: 78 CB 550K motor rebuild
« Reply #150 on: November 30, 2016, 02:35:42 PM »
Any ideas on how to get more torque? I don't want to use vise grips they ruin surfaces in my experience.

Offline DaveBarbier

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Re: 78 CB 550K motor rebuild
« Reply #151 on: November 30, 2016, 03:40:18 PM »
I assume you can't use the original lever for some reason.

I'd get creative. Or you could push on the arm in your picture that's on the left side the one with the small spring. Look at it and see how it works and then push and pull on it.

Or take a 10mm socket on a 1/4" ratchet and use the bolt that's on the drum. If you do this use minimal pressure.

Offline AlekStooge

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Re: 78 CB 550K motor rebuild
« Reply #152 on: November 30, 2016, 04:32:31 PM »
I cut the original off and welded it to a spacer. The last photo is of the knurled part that used to be attached to the shift lever.

I got the drum to move only by tightening or loosening the 6mm bolt and without shifting moving the clutch shaft or shift arm. I don't know if this means I'm good to go? Spinning the clutch shaft is not anymore or less difficult when in one of the gears but there is a slight clicking sound.

I assuming when the wheel sits in the cutaway you are in neutral?

Offline DaveBarbier

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78 CB 550K motor rebuild
« Reply #153 on: November 30, 2016, 04:59:17 PM »
I don't remember if that's neutral or not. You can test it by spinning the clutch shaft and holding the output shaft still (or vise versa).

You should be able to feel when it goes into gear. Not sure of the clicking sound you're referring to. You should be able to go down to 1st gear and then sense that it can't go any more. Then go to neutral and up through the gears to 5th and then, again, feeling that you're at the top and the drum won't advance. It's really not rocket science. Just shift through the gears. If you can't, something isn't right. If the shift forks aren't aligned properly, you'll need to split the cases again. Before that happens, you might be able to see what's going on by removing the oil pan and having a gander.

Offline AlekStooge

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Re: 78 CB 550K motor rebuild
« Reply #154 on: November 30, 2016, 05:33:43 PM »
I'll try it again but I don't feel any sense of the gears being shifted or any kind of resistance from the clutch shaft when rotating it. I don't see how the shift forks didn't align properly when the cases sat flush. I triple checked everything with a flashlight by lifting the cases slightly up and I can see the forks appear to be at the right place looking from the oil pan opening.

If you are referring to the pins on the shift forks being lined up then I can't see those when putting the case together. I thought they fall in place when the forks are hanging.

Offline RAFster122s

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Re: 78 CB 550K motor rebuild
« Reply #155 on: December 01, 2016, 03:41:17 AM »
If you have something to grip with vice grips then pad the surface with several layers of cloth or an old  leather belt between the teeth of the tool and object being held.
David- back in the desert SW!

Offline bwaller

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Re: 78 CB 550K motor rebuild
« Reply #156 on: December 01, 2016, 04:51:12 AM »
I wonder if the collar/spacer centering the outer detent roller may be actually locking both detent roller brackets. They are spring loaded but try to pry them off the drum end. If either seems bound and doesn't move easily remove the 6mm bolt and make sure the collar is correct.

Also the shifter shaft works by it's "hooks" contacting the pins in the end of the drum to rotate it. Be sure the shifter shaft is pushed all the way through the cases so it can engage the pins. As Don mentioned attach a lever or something to have a little more authority on that shifter shaft.

Offline AlekStooge

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Re: 78 CB 550K motor rebuild
« Reply #157 on: December 01, 2016, 09:32:05 AM »
Brent, I got to take a look at all that and see what you mean.

If you have something to grip with vice grips then pad the surface with several layers of cloth or an old  leather belt between the teeth of the tool and object being held.

That is a good idea I tried duct tape before but the teeth broke through.

Offline AlekStooge

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Re: 78 CB 550K motor rebuild
« Reply #158 on: December 04, 2016, 09:46:32 PM »
Update, I took an engine rebuilding class over the weekend. We rebuilt the top end of a CB 350.

I got the gears to shift through and everything seems good. There is a little horizontal play in the shift shaft, is that normal?

I stripped the edges of the fins with a 60 grit and plan on them polishing with a higher grit.

I was recommended to replace the clutch springs since they are inexpensive and I'm already there. I also want to purchase a piston ring compressor. Is there a reason anyone would purchase one with individual bands vs. an adjustable one, like this?
http://bikemaster.com/catalogsearch/result/?q=Piston+Ring+Compressor

Offline RAFster122s

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Re: 78 CB 550K motor rebuild
« Reply #159 on: December 04, 2016, 11:09:45 PM »
FWIW, Someone had shown a set of inexpensive small engine repair (lawn mower) ring compressors made of a red plastic which they had reported worked well.  Two sets could do a sohc4 motor all at once but, realistically you only need one set.  The taller ring compressors may be difficult to remove after slippping the piston and ring into the liner on the second pair as working room disappears quickly.

David- back in the desert SW!

Offline DaveBarbier

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Re: 78 CB 550K motor rebuild
« Reply #160 on: December 05, 2016, 04:29:22 AM »
An engine rebuild class that rebuilt a 350? That's pretty cool and probably a great help.

Play in the shift shaft is normal as it's not fastened by anything.

You totally could replace the clutch springs but I'd first check the manual to see if they're in spec. Same with the friction discs and steel plates. On my 650 I'm reusing all clutch components because they're well within spec.

Regarding ring compressors, I'd do a search on the site (or a google search with "SOHC4" in it to help search the site). Some use fat band clamps and some have found nice small ring compressors. That being said, you don't need a ring compressor. The sleeves have tapers that help the rings slide in. Both my 550 and 650 went in easy.

Glad you're progressing, it's looking good!

Offline AlekStooge

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Re: 78 CB 550K motor rebuild
« Reply #161 on: December 05, 2016, 06:07:36 AM »
It was fun. You'd be surprised how many things you can use a popsicle stick for. The guy went "where's my popsicle stick?" every 20 min.

I believe this is right. I'm not sure how it works. Is the rotor supposed to rotate with the shift drum and press the tab indicating you are in neutral?


Offline DaveBarbier

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78 CB 550K motor rebuild
« Reply #162 on: December 05, 2016, 06:30:18 AM »
Yes, and your bullet connector goes in that loop on top. I'm assuming by rotor you're referring to the little cam lobe.

Offline bwaller

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Re: 78 CB 550K motor rebuild
« Reply #163 on: December 05, 2016, 09:39:00 AM »
The shifter shaft end play is reduced when the clutch cover is installed. The shaft can contact a boss on the cover eliminating most play. Sorry Dave but I think it will be wise to replace those 40 year old clutch springs. Honda still offers springs and I would recommend you replace them.

I have Honda (special tool) ring compressors but rarely use them. I dislike compressors be cause they often scratch the pistons. I prefer using alloy blocks under both #2 & 3 pistons that stabilize them and lower the cylinder onto them then use a screwdriver or my thumbnails to help the rings into the sleeves. If the pistons are held straight, and there is a good taper on the bottom of the sleeves, the job is easier. Trick is to keep the pistons straight, be patient and lower the cylinder evenly.
« Last Edit: December 05, 2016, 09:40:42 AM by bwaller »

Offline SOHC4 Cafe Racer Fan

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Re: 78 CB 550K motor rebuild
« Reply #164 on: December 05, 2016, 09:45:57 AM »
I'd take that class.
1975 CB550K1 "Blue" Stockish Restomod (http://forums.sohc4.net/index.php?topic=135005.0)
1975 CB550F1 frame/CB650 engine hybrid "The Hot Mess" (http://forums.sohc4.net/index.php/topic,150220.0.html)
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Offline DaveBarbier

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Re: 78 CB 550K motor rebuild
« Reply #165 on: December 05, 2016, 10:22:04 AM »
Sorry Dave but I think it will be wise to replace those 40 year old clutch springs. Honda still offers springs and I would recommend you replace them.

Understood :) thanks Brent!

Alek, in your engine class did they cover the part where you need to listen to Brent and not me?

Offline bwaller

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Re: 78 CB 550K motor rebuild
« Reply #166 on: December 05, 2016, 12:47:07 PM »
Hah, #$%* man, don't listen to me. I spent a lifetime keeping Honda producing parts.  ;)

Offline AlekStooge

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Re: 78 CB 550K motor rebuild
« Reply #167 on: December 05, 2016, 10:31:46 PM »
I measured my clutch discs. At first I thought I was within spec which is 3 mm and I'm at around 3.44mm, this was the top disc. Until I measured the other discs and I got around 2.60mm. I did some research and found that one disc is different.

http://4into1.com/ebc-clutch-plate-set-ck1146-honda-cb550-cx500-gl500-gl650/
http://www.cmsnl.com/honda-cb550k-1978-usa_model7222/partslist/E++08.html#results

Clymer's nor the manual on the forum indicate a separate measurement for the "different disc". Can any one confirm this and state what the measurements might be.

Another question I have is about measuring the plates for wear with a feeler gauge. Do you just place a feeler gauge in between a plate and a disc?

Lastly, why does Clymer's and the parts fiche refer to the disc as a friction disc and 4into1 and Barnett refer to the same part as a plate if the makes sense? This is confusing!

Offline flatlander

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Re: 78 CB 550K motor rebuild
« Reply #168 on: December 05, 2016, 11:07:39 PM »
friction discs are the one with the corkey stuff on them. plates are the all metal ones. but people often everything that's in their plates or discs which can make it confusing, indeed.

the discs are measured for wear. you can check their thickness with vernier calipers. mind though, that aftermarket discs or also different models from honda that all fit our clutch hubs, have different original thickness so if the clutch has been replaced before you may be measuring something that was off original spec to start with.

i haven't seen a spec for the top disc.

do you have the clutch with that spring loaded damper plate in it?

Offline AlekStooge

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Re: 78 CB 550K motor rebuild
« Reply #169 on: December 06, 2016, 05:18:57 PM »
friction discs are the one with the corkey stuff on them. plates are the all metal ones. but people often everything that's in their plates or discs which can make it confusing, indeed.

the discs are measured for wear. you can check their thickness with vernier calipers. mind though, that aftermarket discs or also different models from honda that all fit our clutch hubs, have different original thickness so if the clutch has been replaced before you may be measuring something that was off original spec to start with.

i haven't seen a spec for the top disc.

do you have the clutch with that spring loaded damper plate in it?
I don't think so. I don't see anything named damper plate.
http://www.cmsnl.com/honda-cb550k-1978-usa_model7222/partslist/E++08.html#results

Offline flatlander

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Re: 78 CB 550K motor rebuild
« Reply #170 on: December 06, 2016, 10:58:37 PM »
it's no. 7 in the picture and list that you link to.
if you check the honda parts list you'll see if your engine number is supposed to have it or not. if it is, but you don't have one, don't worry. the main thing then is to not leave too much free space in the basket (distance between the top disc and rest of the pack) otherwise it can be a pain to get the clutch adjusted properly.

Offline AlekStooge

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Re: 78 CB 550K motor rebuild
« Reply #171 on: December 07, 2016, 07:30:58 AM »
No. 7 is there.

Was I right about measuring the plates for warpage with a feeler gauge?

Offline RAFster122s

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Re: 78 CB 550K motor rebuild
« Reply #172 on: December 07, 2016, 10:12:04 AM »
If you have a piece of granite it can be used as a surface which is flat to measure the plates for warp using feeler gauge.  But first I would check that they are not worn in thickness.  Some will put new steel plates in based on mileage or if they are bumping up the horsepower on the bike.
David
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Offline AlekStooge

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Re: 78 CB 550K motor rebuild
« Reply #173 on: December 07, 2016, 03:34:13 PM »
I only know of a measurement to be used for warp. Didn't see anything about the thickness in the manuals I looked in.

Offline RAFster122s

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Re: 78 CB 550K motor rebuild
« Reply #174 on: December 07, 2016, 07:44:49 PM »
Ok,  I haven't had to do the clutch, not up on it like others. Followed lots of threads on it... cmsnl has most of the parts for my 74, missing one of the parts, forget if it is the disc or plate...I think the later
David- back in the desert SW!