Author Topic: 550K0 restoration  (Read 2128 times)

Offline dv11250

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550K0 restoration
« on: March 28, 2019, 11:21:47 PM »
 Bought the CB550K0 three weeks ago, US model bought from England with a seized engine.
Having raced karts for 15 years I thought an seized engine rebuild would be fairly easy.

So bike stripped down to the frame in 2 days.

Rocker cover off to discover that one the cam gear screws was down inside the head channel. no option but to split the cam chain and order a new link.

head off and inside pistons are at the top and outside pistons bottom. no movement in the crank at all. :'(

Only 1mm on inside bores to fill with release fluids
soaked in parrifin for three days - no movement.
soaked in Diesel for three days still no movement - applied 2 heat guns until the diesel was bubbling - still stuck
soaked in Liqid-Moly penetrating oil and TQF and heated every night for 10 days.
last night got 0.5mm movement by rocking barrels front to back with a large screwdriver under the fins ay the rear and a 5mm steel plate under the front fins at the two raised points on the front of the crankcase.
Tonight same rocking again while my son tapped the pistons gently with a wooden block and hammer.
30 mins later barrels off - 2 x small ends tight.
 next session tomorrow night

Offline Bryanj

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Re: 550K0 restoration
« Reply #1 on: March 29, 2019, 08:15:53 AM »
You are going to be splitting the cases on that one so just fit new cam chain not link. Would suggest new primary as well.

Offline dv11250

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Re: 550K0 restoration
« Reply #2 on: April 04, 2019, 08:17:14 PM »
Thanks Bryan for the advice on the chains

just working out what all i need for the engine/bike rebuild on get order placed with DS (unless there is anywhere else to get bits).

Got the engine stripped down completley.
Could someone advise what this is screwed into the bottom of the crankcase towards the rotor side

Offline Bryanj

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Re: 550K0 restoration
« Reply #3 on: April 04, 2019, 08:23:33 PM »
It direct a bit of oil to the primary chain, should be two things screwed in leave them there.
Primary damper rubbers are a good idea inside the primary driven gear where starter gear is.

Offline Laverda Dave

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Re: 550K0 restoration
« Reply #4 on: April 04, 2019, 11:29:31 PM »
Good advice Oddjob. Am I correct to assume the same also applies to the big end shells?
1976 Honda 400/4
1977 Rickman Honda CR750
1999 Honda VFR 800FX
1955 750 Dresda Triton
1978 Moto Morini 350 Sport
1978 Honda CB400/4 'Rat' bike
1982 Laverda 120 Jota

Offline dv11250

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Re: 550K0 restoration
« Reply #5 on: May 23, 2019, 06:27:12 PM »
Piston rings arrived this morning from Cruzinimage.

Could someone advise the order they are fitted.
I know the oil ring is in the bottom slot.
The other two rings are black and silver with STD marked on them.


Offline Nurse Julie

  • 1977 CB550/4 Mongrel Brat. 1974 UK 500/4 K1. Honda CD250u.
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Re: 550K0 restoration
« Reply #6 on: May 23, 2019, 07:50:33 PM »
Piston rings arrived this morning from Cruzinimage.

Could someone advise the order they are fitted.
I know the oil ring is in the bottom slot.
The other two rings are black and silver with STD marked on them.
Top ring is silver, 2nd ring down is black.
Like so.....this is a CB400/4 Cruzinimage piston/ ring kit [ Guests cannot view attachments ]
« Last Edit: May 23, 2019, 07:52:58 PM by Nurse Julie »
LINK TO MY EBAY PAGE. As many of you know already, I give 10% discount and do post at cost to forum members if you PM me direct.
https://www.ebay.co.uk/sch/julies9731/m.html?item=165142672569&rt=nc&_trksid=p2047675.m3561.l2562

LINK TO MY CB400/4 ENGINE STRIP / ASSESSMENT AND REBUILD...NOW COMPLETE
http://www.sohc.co.uk/index.php/topic,14049.msg112691/topicseen.html#new

Offline Bryanj

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Re: 550K0 restoration
« Reply #7 on: May 23, 2019, 10:33:41 PM »
With any markings facing upwards.

Offline dv11250

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Re: 550K0 restoration
« Reply #8 on: May 23, 2019, 11:19:40 PM »
Thanks Bryan and Julie,

Rings fitted, new gudgeon pins and circlips, and barrel onto engine.

starting to look like a bike again

Offline dv11250

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Re: 550K0 restoration
« Reply #9 on: May 23, 2019, 11:22:34 PM »
Can any one advise what the 8 green o-rings in the NE gasket set are for.
dont remember taking any off when I stripped the engine

Offline Nurse Julie

  • 1977 CB550/4 Mongrel Brat. 1974 UK 500/4 K1. Honda CD250u.
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Re: 550K0 restoration
« Reply #10 on: May 23, 2019, 11:28:20 PM »
They are silicone O rings for under the valve guides.
LINK TO MY EBAY PAGE. As many of you know already, I give 10% discount and do post at cost to forum members if you PM me direct.
https://www.ebay.co.uk/sch/julies9731/m.html?item=165142672569&rt=nc&_trksid=p2047675.m3561.l2562

LINK TO MY CB400/4 ENGINE STRIP / ASSESSMENT AND REBUILD...NOW COMPLETE
http://www.sohc.co.uk/index.php/topic,14049.msg112691/topicseen.html#new

Online paulbaker1954

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Re: 550K0 restoration
« Reply #11 on: May 24, 2019, 02:08:55 PM »
Thanks Bryan and Julie,

Rings fitted, new gudgeon pins and circlips, and barrel onto engine.

starting to look like a bike again

Looking nice - out of curiosity whats the red thing at back of garage
If you think there's light at the end of the tunnel it's usually another train !!

2016 Yamaha MT09 Tracer
1971 Honda CB500 Four K0

Offline dv11250

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Re: 550K0 restoration
« Reply #12 on: May 24, 2019, 02:36:53 PM »
Countax lawnmower

Offline paul G

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Re: 550K0 restoration
« Reply #13 on: May 24, 2019, 03:56:36 PM »
How big is your lawn  :o
Honda CB400 4
Honda CB550 K3 (sold)
Honda CB750 UK K1
Kawasaki Z650 C2
Kawasaki Z650 cafe racer (Sold)
Honda CD175 sloper

Offline dv11250

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Re: 550K0 restoration
« Reply #14 on: May 24, 2019, 05:15:15 PM »
Takes over an hour to cut with the tractor lawnmower, never mind doing the edges.

 

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