1976 CB550F1 (what have I let myself in for) Project

[eight0]

Out of interest, the  lowest 2 holes in the emulsion tubes in my carbs are smaller than the rest. I would assume this is because it's an F1 model.

If I'm right in thinking, that make the bike run richer at idle than if the holes were all the same..?

That would make sense as the plugs were well sooted up and I was running it without any sort of air filter and 40 pilots from NRP. But again as you rightly say, there's little point to all this until I get the air filters.

[K2-K6]

"If I'm right in thinking, that make the bike run richer at idle than if the holes were all the same..?"

They shouldn't affect the overall mixture volume as that's controlled for maximum flow by the jet size.

What the emulsion "strategy" of any system does is to try and improve atomisation of fuel droplets as refining the size will effectively give improvements in mixture quality, making it burn more evenly and so smoother throttle response.

[eight0]

I had the carbs synced professionally last week. I still had a hanging idle but I resolved that by cleaning the advanced mechanism and using some thinner grease.

I took the bike for its first lengthy ride on the weekend between the surrey cafes. Overall it rode pretty good, apart from a slight stumble off idle when under load it pulled well through the revs.
I will be spending a lot more time on the carbs, but as I've said previously, I will probably try and work through that on my own rather than ask on here.

One issue that has come to light, is the rear brake plate eating into the hub causing. There were quite a lot of aluminium shavings which I found sat in the recess of the rims. The plate already had a bit missing which I knew about when I put it on, but I didn't think it would be a problem.

[ Guests cannot view attachments ]

I've ordered another hub from Fleabay so hopefully that will be ok.

There are also a couple of oil leaks, there is a small amount of oil on the fin above the base gasket on the left side. Not sure where the source is yet.

Here's a video of it running, it's before I sorted the idle hang or had the carbs professionally synced, so you can hear the revs stay up after I blip the throttle.

https://youtu.be/2MveXqWVcXQ







 

[K2-K6]

Rear brake plate, are you certain you've all the spindle spacers in all the right places?

Should be able to torque the axle fully without anything touching anything else. 

[eight0]

Pretty sure yeah, the wheel turns freely, doesn't feel like it's binding or catching at all.
I need to look at it more closely to see if I can work out why it's happening.

[eight0]

Ok I know what's caused it.

I'm missing part 12.

[ Guests cannot view attachments ]

I'm surprised I didn't hurt myself riding it! The left wheel spacer was just being held in place with the sprocket plate seal which had destroyed itself.

[ Guests cannot view attachments ]

Seems unobtanium. Might have to see if I can get one machined.

[K2-K6]

Yep, lucky to get away with that as locking rear wheel is not funny 

Probably the design of the chain adjustment plates that largely held it in place.

Decent engineering shop should be easily able to replicate if you can't find one.

[Nurse Julie]

Ok I know what's caused it.

I'm missing part 12.

(Attachment Link)

I'm surprised I didn't hurt myself riding it! The left wheel spacer was just being held in place with the sprocket plate seal which had destroyed itself.

(Attachment Link)

Seems unobtanium. Might have to see if I can get one machined.

I'll have a look in the morning, we may have one.

[eight0]

Thanks Julie. Let me know, that would be amazing if you do.

[Nurse Julie]

Thanks Julie. Let me know, that would be amazing if you do.

There you go. I will PM you later as I'm just cooking dinner 😁
[ Guests cannot view attachments ]

[SteveD CB500K0]

And does Elvis the Dachshund have anything to say about this?


Sent from my iPhone using Tapatalk

[eight0]

Amazing! Love this forum. Thanks Elvis (and Julie)

[Bryanj]

I have the sizes in my parts book and that seal is nothing special, you should get one anywhere.

[eight0]

Thanks Julie, part received and installed. Haven't ridden it yet (Bloody rain) but it all seems good.

[Nurse Julie]

Thanks Julie, part received and installed. Haven't ridden it yet (Bloody rain) but it all seems good.

Great, it'll probably handle better now 😁😁😁. The weather looks pretty shite for the weekend as well 😭😭😭