CB550 Tuning Advice

[badger_eng]

Just set the tickover to 1100 then you won’t need to change the rubbers or do any searching 😬

[Bryanj]

When in workshop for a living yes you could get a low tickove but it took time to set everything spot on not just within tolerance and as all sevicing was done on a specified time basis you simply couldnt do that, according to Honda you could do a complete crank change with full engine dissasembly in 8 hors from wheeling the bike in to riding it out including cleaning, sorting shells and checking all parts.
The only Honda factory time i could meet was the CX 500 cam chain tensioner mod and that only because i ignored some of the taking off parts and had a 3/8 drive air gun plus did a lot

[Oddjob]

The problem with just ignoring the clutch rattle is it accelerates the primary chain wear. The constant back and too transfers to the primary chain and it can only take so much before that starts making noise as well.

For some reason the 550 is more susceptible to the clutch rattle than the 500, taken a few baskets apart in the last few years and almost every 550 had rock hard damper rubbers with movement on the gear because of it. About 30% of the 500 clutch baskets had hard rubbers and gear movement. Odd as the rubbers are older and look identical.

There is supposed to be someone making some 500/550 clutch damper rubbers but when they are available is anyones guess. The only other supplier is in Europe and he refuses to send them to the UK after the B word. I ordered 5 sets a few years ago after asking a European member if he’d order them and send them on. Roo had a set, think one of the Orkney members had another for his 550k3 and Grommitdog had a set. I kept the last 2 sets for personal use. The difference when fitted is quite apparent, no movement at all on the gear and the k3 owner said it quietened down his engine so it does work.

[Sesman]

Too true, Ken.

I’d prefer to cure the backlash, but for now I’ll tolerate it. The basket is shimmed to zero float, and i renewed the primary drive chain and rubbers during the rebuild. In all fairness the motor is extremely smooth under load; surprisingly so in fact. I just have to purge this black granule shit contaminating the carbs. I doubt I’ll get round to soon. I’ve bought replacement fuel lines and we’ll see.

Incidentally, if you didn’t already know, Yamaha are cursed with this very same issue with their CP3 motors. The clutch rubbers deteriorate really quickly and there are plenty of offers of replacement mods on the net. I own an MT-09 SP, brand new in July this year and after only 3800 miles the basket is showing signs of backlash: rumbling noise at tick over, disappearing with clutch engaged or under load. Makes the gear change slightly more ‘snatchy’ at low speed too.

[Oddjob]

Have you checked the basket gear for movement Phil?

I do have some 550 baskets lying about. Just sold one in fact. Might have another with no movement.

[Sesman]

Hi, Ken. Yes, the basket shifts back and forth about 1/8 inch or so (probably slightly less, but I wasn’t too bothered at the time). It’s like the rubbers have shrunk. Though I’ve no doubt they have also hardened.

Surprisingly the original primary drive rubbers were in superb condition, comparative in both size and hardness to the new replacements. I replaced them anyway.

It’s not a disaster, just a ‘they all do that sir’ imperfection. On the basis that the original drive components were in perfect condition, I’ll probably persevere rather than fiddle. Hang on to those parts mate…you may need them. Have you seen what CMNSL want for a basket? HOLY shit. Bearing in mind this bike has only done 17k miles.

[deltarider]

Although I'm not saying it must have made a difference, I have maintained using engine oil that's nice to rubber parts. In my case it has mostly been Castrol's High Mileage 15W-40, which isn't even a specific motorcycle oil. So far I have no indication of hardened rubbers (knock on wood). I have read a comment here and there where somebody stated that Castrol in general was keeping rubbers more supple than others, but... - I have no science to prove it - so this remains anecdotal. I have also read somewhere that manufacturer Honda favoured Castrol back then after a test: Castrol had been quickest in arriving at the camshaft. That's where wear would take place first in the OHC engines of that era.
I'm out of popcorn, so I cannot promise you I will read the next posts.

[Sesman]

Incoming…..😁😁

[McCabe-Thiele (Ted)]

I suspect  Deltarider is referring to plasticisers that many high end engine oils have as an additive to keep seals like rear mains in car engines supple. They have been around for a while, pretty much standard in thin synthetic oils. They are not generally listed on the tin, they might be listed in the technical specification.