Topic: Happy easter. Look at my disaster.

[Lostboy Steve]

So I was going to change sprockets and while I was in there the seals because I had a little leak. Well, I pulled off the cover and oil went everywhere. It looks like the oil pump is leaking. Any idea what a good plan of action is here? Secondly, I ordered an 18 tooth sprocket thinking it was 1 tooth larger than stock only to find my 77 550 has a 15tooth on it. I am all screwed up.

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[Lostboy Steve]

So as it sits right now its setup 15/34. Maybe that's why I feel like its screaming down the highway.

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[Lostboy Steve]

I cant wrap my head around if this is even worth the effort now, or if I should just slap that 15/34 back on. I still want some instant pickup.

[TwoTired]

If it were a 15/30 combo, the front sprocket would spin 2 times for the rear wheels one turn.

A stock 17/37 Cb550 spins the front sprocket 2.18 times for each one rear wheel revolution.
The common 16/37 mod spins the front sprocket 2.31 times for each one rear wheel revolution.  Better acceleration, buzzy on freeway.

A 15/34 spins the front sprocket 2.27 times for each one rear wheel revolution.
An 18/34 combo spins the front sprocket 1.89 times for each one rear wheel revolution.  This would be quite a dog from a throttle twist perspective, imo. (wear out the clutch faster, too.)

Why do you have a 34 T rear sprocket?  Only the Cb500s had those stock.


I will warn that if you go back to stock gearing, that oring chain (what is it's width?) will likely chew into the countershaft seal, if it hasn't already.

[Lostboy Steve]

Thank you two. I never counted the teeth when I got the bike. No The seal is ok I am changing to a regular chain anyway though. I couldn't tell you why or when the sprockets were changed. I wasn't planning on keeping this newly purchased 18t sprocket. As of right now the way it was 15/34 was "quick" but I was always looking for another gear even at 55-60 mph. Its not that it can't do 95, but it is absolutely screaming at that speed.

The thing that really blows my mind is how, when i got this bike, it was frozen in time. Nothing seemed changed ever. All of it looked original and was there. What is your opinion on my oil leak? I think its just the multiple o-rings that are probably dry rotted from its 25year hibernation. Its the only rubber on the bike that hasn't been changed.

[TwoTired]

Oil pump leak is likely the O rings.  There are some that mate the pump body to the engine case.  And there is one large thin one under the pump cover.  The later seems to be the hardest to find, as Honda wanted to sell the entire pump, rather than just the o ring to seal it's cover.

There were some threads that resolved the dimensions in the past.  I don't recall sources other than BryanJ having some.  Don't know if that is still the case.

[lucky]

It does not look that bad.

The fact that you had a small oil leak has nothing to do with ordering the wrong sprocket.
They are separate issues.
Don't BACKPACK meaning do not scrape all of your problems into on big overwhelming pile.

No go get something  to eat and relax.

[LesterPiglet]

Look on the bright side, at least you had that exhaust bandage to soak up the oil. Saved your workshop floor.   

[dave500]

ive always found the standard gearing works fine,putting a 37 rear on a 500 makes it like you've lost 5th gear!,i imagine using a 34 on a 550 is like 1st got taller and 5th will lug?thats with the standard 17 front of course.

[Lostboy Steve]

Look on the bright side, at least you had that exhaust bandage to soak up the oil. Saved your workshop floor.   

No it didn't. When I popped off that cover I would say about a 1/2 qt of oil went right on the floor. Its not that I ordered the wrong sprocket, its that someone changed the gear ratios.

[Frostyboy]

Getting back to the oil leaks. I did my oil pump late last year. Still dry as a bone. I used genuine part numbers for the outside o rings, but as mentioned the one for the cover isn't listed. All the searching I did found most are using 46x2mm for the cover. I measured the boss on the pump at 44mm. I ordered a 44x2mm from a bearing supply & it fitted perfectly. Still doing the job.

[Deltarider]

Why do you have a 34 T rear sprocket?  Only the Cb500s had those stock.

The 550K3 [ED] had them too, to market that particular model as the tourer version of the somewhat sportier F. Just for the record.

[Don R]

IMHO a 15 tooth is a tight turn and works the chain a bit harder. I'd prefer a larger front sprocket and a larger rear to work with it. Buut I'm a 750 guy, could be wrong.

[Lostboy Steve]

Why do you have a 34 T rear sprocket?  Only the Cb500s had those stock.

The 550K3 [ED] had them too, to market that particular model as the tourer version of the somewhat sportier F. Just for the record.

So is that what i have then? But these didnt come with a 15 front did they?

[Deltarider]

No, all 500 and 550s had 17 teeth in front. You've lost two. Of age?

[Lostboy Steve]

wtf. Well I exchanged the 18 for a 17 and will see how that feels on the turnpike. Then, will go from there.

[TwoTired]

wtf. Well I exchanged the 18 for a 17 and will see how that feels on the turnpike. Then, will go from there.

The early Cb500s had a final reduction of 2.00 using the 17/34 sprockets. The primary ratio in the trans case was 2.00.
The CB550 had a final reduction of 2.176 with the 17/37 sprockets. The primary ratio in the trans case was  3.063.

Unless you are highway cruising for max economy, a 34T rear sprocket is too tall for gearing.  None of the American continent Cb550's had a 34T rear sprocket.  The European bikes had lots of weird combos from the Honda parts bins.  Unless you know you have a European import, just ignore the parts lists from there.

The Cb550 is gonna be a real dog on acceleration with a 17/34 combo, particularly with oversize tires, imo.  And, it is unlikely to be able achieve 98MPH in top gear...  maybe in fourth though, with the engine screaming.  I don't know why you'd torture the bike and clutch in this way.

[Lostboy Steve]

I'm not intentionally doing so. If its that terrible I'll have to source a 36 tooth rear or get a stock 37. Again I could just leave it as is with the 15/34 setup.

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[Deltarider]

Twisted, don't pay too much attention to what TT wrote here. It is his way of reacting on anything I post. Look elsewhere how many words he had to spend on my reaction 'I'd say it's not abnormal' to a miserable voltagedrop of 1 Volt. Pages just to put me in my place.

Here goes.

The European bikes had lots of weird combos from the Honda parts bins.

 
The weird combo is in the glasses of the beholder. We can't help him with that. Advice for him: don't leave the USA ever. He may find himself in a weird country. He couldn't cope with that.

Unless you know you have a European import, just ignore the parts lists from there.

But (sigh)... there is only one Parts List CB500K3/CB550K3/CB550K4 that deals with all models for all area's.
And what if a US or Canadian reader is interested to accentuate the touring character of his 550K3? Just like Honda did for some European markets deliberately. The parts bin. Don't make me laugh. Both 34 and 37T were widely available and still are. The 550K3 [ED] was to market a tourer version of the somewhat sportier F2 (see below).

The Cb550 is gonna be a real dog on acceleration with a 17/34 combo, particularly with oversize tires, imo.

 
'imo'... not before the end of the line and not even in capitals. I doubt TT has any experience riding one. I have and I can assure you acceleration is more than adequate. The K3 is not the quickest but that's due to it's overall weight.

And, it is unlikely to be able achieve 98MPH in top gear...  maybe in fourth though, with the engine screaming.  I don't know why you'd torture the bike and clutch in this way.

So what? If you still want that kind of bike, desire that touring character? Seems to me the one screaming here is TT...
Notice the anger, the agression? It's ment for me and I feel sorry you all have to witness this again. It's frustration all out. My advice: never ever correct TT on even the smallest detail or he will haunt you for the rest of your life.

[Deltarider]

And I could include the test results that indicate top speed was higher than 98 Mph (any K3 should easily do 165km/h), but I know at forehand what TT's reaction will be: these magazines were paid by the advertiser. I have adressed the lack of logica in that remark before (Was Honda really the only advertiser? ).
The 550K3 [ED] was ment as the tourer version next to the F2. There's nothing weird about that. My information was and is free. Do with it whatever you want. What do I care.
I recommend the standard 17T in front however.

[dave500]

the primary chain ratio is the same for 500s and 550s,the primary reduction is done with a different clutch basket ring gear and the primary shaft gear.

[TwoTired]

the primary chain ratio is the same for 500s and 550s,the primary reduction is done with a different clutch basket ring gear and the primary shaft gear.

No argument there.  I was just reading from the Honda shop manual pages on tech data for the 500 and the 550, where it talked about primary reduction.  Chapter  13.   I had assumed it was the chain cogs.  I'll go back and fix it, Dave.

As for delta,  ...he is simply paranoid, irrational, and insane.

[dave500]

no worries,yeah the cranks are identical on the two engines as is the primary chain cush drive hub,i think the idea of the taller reduction in the 550s was to spin the transmission faster for slicker shifting and also to reduce the load on the clutch by gearing down the final drive to compensate?

[Lostboy Steve]

First of all, I am staying on the beaten path of gear ratios here. Delta, Thanks you. That information is very interesting and helpful. It is also very believable that they would market a touring version in Europe where we all know some of the highways are without a speed limit. I won't lie, I like to cruise at 85mph. Why? Because I do. For this the 17/34 setup might be wonderful. Remember, when these bikes were made, the united states had 55 posted on most of its highways. If I did 65 on the pike, I'd get run over. Twotired, thank you. Your information now and in the past has also been extremely helpful. Dave, as always its a pleasure receiving knowledge from you. I think this subject is more or less a matter of personal opinion. I will start by running the 17/34 and let you all know what I think. I will also post (as accurately as I can) cruising, and accelerating data as well as a "personally comfortable" top speed result. I might ad that as you may or may not know my 550 isn't stock. I ported the head and had a 3 angle valve job done, amongst other engine work. It also has a uni filter in a lidless (cuz I cant source one) airbox and the 4 into 2 "swept" exhaust. Jetted correctly with Hondaman ignition and dyna 5ohm coils with new wires. I also have the EBC HD clutch & springs. Currently she gets up and goes QUITE well. Anyway again, thank you all for the insight and entertainment.

[Duanob]

My thougths if you plan on keeping and riding the bike put it back the way it was supposed to be set up and then make small modifications as you see fit.

You can get everything you need for the drive train here:

http://www.powersportparts.net/SearchResults.asp?Search=JT+sprocket

I wouldn't use the 18T on the 550 for clearance reasons. Definitely don't use an o-ring or x-ring chain for the same reasons. It can chew through the casings. Just a plain 530 x 100 link should fit, all things being stock parts (17t x 36T or 37T).

I put a 36T on the back of my 550K, it doesn't climb the RPMs as fast but it cruises on the hiway a bit nicer. I'm not always searching for that last gear like with the 37T rear at 60mph. Just a thought.