CB550k1 US Import - UK registration

[davidcumbria]

Glad you fixed it. These two videos show how the rocker shaft issue can affect the top end noise and maybe helps with a good / bad engine sound though everything sounds noisy on YouTube !

https://youtu.be/MDIkDb_HhKw

https://youtu.be/gDDK6ZOxmno

[Oddjob]

It would appear the 550K1 still had the small rocker shafts that plagued the 500, I'd certainly think about checking them and seeing if the camcover has elongated or the shafts are showing damage.

[Laverdaroo]

Successful fix that, how satisfying


Sent from my iPhone using Tapatalk

[juitz]

Took the bike out for its first long ride yesterday.

Definitely a few things to address, specifically the sub-optimal idling. But it did a round trip to work (70 miles) and got back in one piece.

Thankyou so much to everyone with all the help and advice over the last 18 months with this project. Bunch of legends!

Like i said, few things to address still but to me a successful build.

Next up will be a 500 or 550 restoration to original.

I'll keep posting on this thread as I am sure I'll find a few more issues 😂

[juitz]

I've got a bit of a head scratcher.

The bike will struggle to return to idle of 1100rpm when hot. It will sit at around 2000rpm. Tweaking the idle screw can help but it's overly sensitive.

So I thought to double check for any air leakage into the carbs, rubber boots, seals, etc.

Was a bit short on wd40 so sprayed a bit of carb cleaner at the carb area. When I spray the inlet manifold my engine will stall. Tried it with wd40 and nothing really happens. Sprayed carb cleaner again and it stalls again.

The engine is hot but I can't see anything being sucked in, it looks like it just evaporates. I'll try again with a cold engine but bit stumped why it stalls in the first place and why with one and not the other?

Maybe need to replace with new oring seals? I happens on cylinders 1 and 4 by the looks of it.

[Oddjob]

It stalls with one but not the other because one is very volatile and the other isn't. What colour are the plugs? Have you checked the rubber insulators for cracks? Are the alloy washers on the vac screws? Probably looks like 1 and 4 because those are the outside cylinders so easier to get the carb cleaner to them.

Have you changed the orings on the inlet manifolds at any time?

[juitz]

It stalls with one but not the other because one is very volatile and the other isn't. What colour are the plugs? Have you checked the rubber insulators for cracks? Are the alloy washers on the vac screws? Probably looks like 1 and 4 because those are the outside cylinders so easier to get the carb cleaner to them.

Have you changed the orings on the inlet manifolds at any time?

Rubber insulators are brand new and I put new orings that came with the vesrah seal and gasket kit I purchased from David Silvers. But I think i am missing the alloy washers on the vac screws you mentioned. Missed these from what I can remember so i'll get some on order if I can find the part no (not seen in the parts manual)

[Multiman]

This is Julies eBay shop.
Contact her direct for a better price
https://www.ebay.co.uk/itm/166216111052?_trkparms=amclksrc%3DITM%26aid%3D777008%26algo%3DPERSONAL.TOPIC%26ao%3D1%26asc%3D20221115143056%26meid%3D156272f5c3694aef9986c9177680b970%26pid%3D101612%26rk%3D1%26rkt%3D1%26itm%3D166216111052%26pmt%3D0%26noa%3D1%26pg%3D4375194%26algv%3DRecentlyViewedItemsV2%26brand%3DUnbranded&_trksid=p4375194.c101612.m4236&_trkparms=parentrq%3A59d3b62a1890ad99327019b3ffff90e4%7Cpageci%3Af1923f31-2316-11ee-a5af-42909c03a673%7Ciid%3A1%7Cvlpname%3Avlp_homepage

[juitz]

So decided to take the carb inlet manifold off as I had a suspicion that I had not masked ithe mating surface during painting. Sure enough it was painted and I could see small clumps of paint. Removed the paint wire a copper wire wheel and reattached the carbs. Did the carb cleaner test again and it doesnt stall anymore 👍

Went through the carb vac sync again as well and seems ok-ish.
The bike still hangs at around 2k but it does drop back to 1300rpm idle after a second or two. I did note though pressing on the brass caps on the slider mechanisms it will return to idle immediately. Does this indicate a sticky mech?
Throttle cables look to have enough slack.

Also, bike revs ok up to a semi aggressive throttle twist, but going full WOT instantly the engine will cutout?

[Bryanj]

Sounds like you may have bench synced with the slides too high

[juitz]

Sounds like you may have bench synced with the slides too high

I'll go back and do the bench sync again - went straight into vac sync after the manifold changes.

[juitz]

Hi everyone, it's been a while.

Had family visiting from overseas so been busy playing host and not playing with the bike at all!

Finally getting back to it over the last few weeks and I'm still stuck on the carb tuning at idle. I'm now at the point where I'm looking at further increasing the idle jet size to a #45 and see if that improves things.

Does anyone know where I can get them in the UK or EU? Have looked at US sites and it's usd$60 to ship!!!

[Johnny4428]

https://www.ebay.co.uk/str/siriusconsolidatedinc

Got mine from here.

[McCabe-Thiele (Ted)]

FWIW when I bench synched my 400 I went for a small gap on the sliders I used an odd sized drill shaft it was 3/32" iirc.

I worked on the basis that I could speed the idle up easily by adjusting the one screw on the throttle link.

[Laverdaroo]

Hi everyone, it's been a while.

Had family visiting from overseas so been busy playing host and not playing with the bike at all!

Finally getting back to it over the last few weeks and I'm still stuck on the carb tuning at idle. I'm now at the point where I'm looking at further increasing the idle jet size to a #45 and see if that improves things.

Does anyone know where I can get them in the UK or EU? Have looked at US sites and it's usd$60 to ship!!!

Dave,Im off over there next week but not back until crimbo (21st Dec), happy to drag anything back over for you if it helps mate. I'll be putting in 'a jets' order anyway when I'm there.
Let ,me know......