Topic: Apologies (CB550)

[Chappy]

Apologies - UK here 

 Delkevic 4-1 on ebay although they said it wouldn't fit my 550 76'

http://www.ebay.co.uk/itm/4-1-Exhaust-System-Stainless-Silencer-Classic-Straight-CB550F-Supersport-77-78-/291699796721?hash=item43eaa9aaf1:g:5h0AAOSw5ClXx0OV

[flatlander]

did you ask them why? the head is the same and i'm not aware of any big difference on the frame between F1 and F2 models.

[flatlander]

actually, check here on the delkevic website: http://www.delkevic.us/index.php?route=product/product&product_id=41433&search=cb550f&Title=Full+System+to+fit+CB550F+Supersport+%281975-1977%29+with+Classic+Straight+Universal+Muffler+and+Stainless+Steel+4-1+Headers&SKU=COM320B

there the same exhaust is listed for all F models from 1975 onwards. i don't know who you spoke to but this makes more sense.

[Chappy]

actually, check here on the delkevic website: http://www.delkevic.us/index.php?route=product/product&product_id=41433&search=cb550f&Title=Full+System+to+fit+CB550F+Supersport+%281975-1977%29+with+Classic+Straight+Universal+Muffler+and+Stainless+Steel+4-1+Headers&SKU=COM320B

there the same exhaust is listed for all F models from 1975 onwards. i don't know who you spoke to but this makes more sense.

The UK website doesn't state the 75-77.. Super odd.

did you ask them why? the head is the same and i'm not aware of any big difference on the frame between F1 and F2 models.

I have emailed Delkevic and am awaiting a response (the response from Ebay was from Delkevic too but thought I would contact direct).  Delkevic would be ideal, straight muffler looks half decent too.

Cheers both.

Edit - Product Code COM320B for both USA and UK 550 full exhausts so maybe I'm onto a winner.

[flatlander]

yes it's the same product. sorry, didn't realise you're in the UK.
i would expect it to fit both F models.

[IRISHCBRACER]

http://www.cb750cafe.com/blog/stainless-steel-4-into-1-exhausts-for-cb500-cb550-now-available-399-only/

[Chappy]

Afternoon all, it's been a while.

I thought I would revisit the seized engine. I took the rocker cover and split the chain with a bicycle chain splitting tool and removed the camshaft and cylinder head.  Number 1 pistons looked a bit gunked up so I put pentrati G oil onto all for.  Made a cup of tea and let it soak for half and hour.  I then poured some petrol onto them, and lit it.. cleaned them up, added more penetrating oil and put a spanner onto the crankshaft. It moved!

I then pulled the cylinder block and removed the pistons to let them soak for a bit. The engine itself (apart from it being seized when I obtained the bike is immaculate (no wear marks or gauges visible anywhere)

Could I have some advice for the next steps - cleaning the cylinders. 

 

[calj737]

You can purchase a honing stone and refresh the bores if they are still within spec. Fresh rings, and reinstall. This of course depends entirely upon accurately measuring the bores and determining whether everything is within wear limits. Also, don't forget to measure the piston ring end gap before assembling the motor.

[Chappy]

     

     

[calj737]

Looking at the picture of the rusted bore, I'd be dubious that a hone will be acceptable. I'd expect a re-bore and oversized pistons are in your future. 

[Chappy]

Bugger.  I'll give it a rub.. and post the results.

Cheers : thumbsup :

[Chappy]

 

I spent 5mins on each with 800 wet and dry, there is visual scarring but most of the corrosion was built up on the cylinder rather than into it if that makes sense.

What's the verdict? 

: drum-roll :

[b52bombardier1]

The verdict? Find a truly competent machinist with calibrated measuring tools and follow his advice to the letter. He should measure for next oversize diameter, taper and out of round condition.  Don't buy anything until he tells you what to purchase.

If he's really good, he won't start your bore until he has that new oversize piston in hand. This allows him to very precisely tailor his bore to that particular set of pistons. The tiny clearances needed demand this level of precision.

Rick

Sent from my SAMSUNG-SM-N900A using Tapatalk

[calj737]

 

I spent 5mins on each with 800 wet and dry, there is visual scarring but most of the corrosion was built up on the cylinder rather than into it if that makes sense.

What's the verdict? 

: drum-roll :

The verdict based upon these pictures? Same as before. Measurements, measurements, measurements. And all discoloration needs to be removed either by a hone or machined bore.

[RAFster122s]

Align bore them as well to restore about 5% loss because of the drift of material used for the cooling fins on cylinders.  That might require it to go up a size... so, measuring is definitely required.