Topic: CB550 Motor Build

[flatlander]

ok that's clear then.
i'm pretty sure the 61mm that camrector mentions are dynoman, as wiseco doesn't make them larger than 59mm for the 550/500. if those fit without mod with the 126-20 is still unknown.

[SOHC4 Cafe Racer Fan]

61mm could also be the ones developed by Brent.

[flatlander]

brent mentioned 60mm.

[SOHC4 Cafe Racer Fan]

brent mentioned 60mm.

My mistake.  Sorry.

[Camrector]

Ok so here's a question or maybe a few. The  dynoman 61r Pistons are 11.5-1 cr and have larger valve reliefs made for the dp335 cam. Cam numbers Lift 335 / 339
Dur 285 / 295 . The Megacycle 126-20 is .363".333"  259° 104.5°. Do you guys think these would not require milling?
Also what do you guys think of that cr? My bikes only get 94 octane no ethanol.

[flatlander]

363 vs. 335 intake lift - that's a huge difference. nobody can guarantee you it will fit with those pistons out-of-the-box unless they've tried it.
you can try asking dynoman but buzz would probably not promise anything either, unless it's about one of the webcams he carries.
i personally would only trust own measurements and be mentally prepared for having to cut.

[Camrector]

Duly noted Flatlander thanks. Nils is finishing up vapor blasting everything today,
So soon we will have all pretty,sparkling, cases and covers to begin with! I'll post tons of pics of those. Still open for discussion on top end.

[calj737]

Correct, 59 Wisecos, 126-20. The relief became necessary due to OS intakes and the cam. I can't which component necessitate it as I don't alternative cam or head to compare against.

But if it were me, I'd definitely be upping to OS valves regardless of the -20 or -00 cam. They're a much better benefit than you can get elsewhere if you're already replacing the valves.

[Stev-o]

Nils is finishing up vapor blasting everything today,
So soon we will have all pretty,sparkling, cases and covers to begin with! I'll post tons of pics of those. .

So you will be running "naked" cases?  [no paint/powder]

[Camrector]

Thinking about it Stev O

[Stev-o]

Thinking about it Stev O

I'm doing it on my Kawasaki 750 H2.  Nils has already vapor'd the entire motor. But the Triples did not come painted from the factory...

[SOHC4 Cafe Racer Fan]

From what I've heard from Cal, vapor blasting yields a peened finish that is supposed to be more stain resistant.  I wonder if the aluminum once blasted is still prone to oxidation.  I don't have experience or enough knowledge of the process.

[Retro Rocket]

From what I've heard from Cal, vapor blasting yields a peened finish that is supposed to be more stain resistant.  I wonder if the aluminum once blasted is still prone to oxidation.  I don't have experience or enough knowledge of the process.

I've seen a wet blasted {similar process} engine that was still perfect after about 7 years in the bike {750 Honda} with no other coatings, I'll be having an engine wet blasted very soon...

[bwaller]

Ok so here's a question or maybe a few. The  dynoman 61r Pistons are 11.5-1 cr and have larger valve reliefs made for the dp335 cam. Cam numbers Lift 335 / 339
Dur 285 / 295 . The Megacycle 126-20 is .363".333"  259° 104.5°. Do you guys think these would not require milling?
Also what do you guys think of that cr? My bikes only get 94 octane no ethanol.

It's just wise to test assemble with the gasket thickness you plan to use to check all clearances.

D-man offers three different 61mm CR options if you're concerned. The 500/550 heads have a nice squish shelf built in so as long as the piston crown design takes advantage of this (no more than 1mm clearance) there is adequate turbulence and efficient combustion so detonation is rarely a problem in these engines.

[Camrector]

Thanks so much Brent. Still waiting on a reply from Mr. Rieck, about the head work and the Pistons.
Id like to use yours if he still has them.

Gentlemen after seeing the photos Nils just sent me, I would be an idiot to put paint on this. Wow
He is a wizard.

[flatlander]

yes test assemble and measure clearances, no matter what combination you end up using.
forgot to mention: i also use 1mm oversize valves with the 126-00 and wiseco 59mm and didn't have any issues.

you could consider clear-coat if you want to avoid oxidisation or staining. i myself left the blasted cylinders and head, and polished cover naked aluminium as i want a more "matured" look. no long-term experience yet but i've ridden it for about 1/2 year through rain, sun and everything and so far it didn't noticeably change appearance.

[calj737]

From what I've heard from Cal, vapor blasting yields a peened finish that is supposed to be more stain resistant.  I wonder if the aluminum once blasted is still prone to oxidation.  I don't have experience or enough knowledge of the process.

Aluminum will still oxidize after vapor blasting, but it is quite a bit different in its effect. VB provides a layer of protection and does make maintaining the finish far easier.

[Retro Rocket]

From what I've heard from Cal, vapor blasting yields a peened finish that is supposed to be more stain resistant.  I wonder if the aluminum once blasted is still prone to oxidation.  I don't have experience or enough knowledge of the process.

Aluminum will still oxidize after vapor blasting, but it is quite a bit different in its effect. VB provides a layer of protection and does make maintaining the finish far easier.

Thats interesting Cal, the wet blasting I mentioned does not oxidize at all...As I stated above, 7 or more years and it looks perfect...

[calj737]

It doesn't discolor the way raw aluminum will, but aluminum oxidize without a treatment on it. The effect of oxidation on vapor blasted aluminum is very different in its appearance and is nearly distinguishable as it doesn't discolor and chalk up.

[Retro Rocket]

It doesn't discolor the way raw aluminum will, but aluminum oxidize without a treatment on it. The effect of oxidation on vapor blasted aluminum is very different in its appearance and is nearly distinguishable as it doesn't discolor and chalk up.

I understand, what I'm saying is that the guy I know that does "wet blasting" says that it seals the surface and prevents oxidation, and from what I've seen, it does, absolutely no discernible signs of oxidation what so ever...  If it doesn't discolor and chalk up, what exactly does it do..?

[calj737]

I can't say about "Wet blasting" and its effect. Perhaps its a different method than vapor blasting, though they appear similar? I can only relate what has been cautioned to me, the parts I've seen in person and the before/after/longer afterwards. I would describe the oxidation as a "dulling" of the sheen if that describes it. Perhaps Nils could offer better insight as a professional.

[Retro Rocket]

I can't say about "Wet blasting" and its effect. Perhaps its a different method than vapor blasting, though they appear similar? I can only relate what has been cautioned to me, the parts I've seen in person and the before/after/longer afterwards. I would describe the oxidation as a "dulling" of the sheen if that describes it. Perhaps Nils could offer better insight as a professional.

I wonder if something as simple as wiping down occasionally with WD40 or something similar would stop the dulling. Wayne says the his low pressure wet blasting is NOT vapor blasting, I must go over and have a look...

[Stev-o]

I can't say about "Wet blasting" and its effect. Perhaps its a different method than vapor blasting, though they appear similar? I can only relate what has been cautioned to me, the parts I've seen in person and the before/after/longer afterwards. I would describe the oxidation as a "dulling" of the sheen if that describes it. Perhaps Nils could offer better insight as a professional.

I wonder if something as simple as wiping down occasionally with WD40....

From Nil's Vapor thread...


"I've just started using an excellent protectant called ACF50 on things that I blast. Folks that have been using it swear by it, and it is in fact more expensive per gallon then the airport-grade single malt scotch I drink."

Apparently, it is an anti-corrosion compound....

http://www.acf-50.co.uk/

[Retro Rocket]

I can't say about "Wet blasting" and its effect. Perhaps its a different method than vapor blasting, though they appear similar? I can only relate what has been cautioned to me, the parts I've seen in person and the before/after/longer afterwards. I would describe the oxidation as a "dulling" of the sheen if that describes it. Perhaps Nils could offer better insight as a professional.

I wonder if something as simple as wiping down occasionally with WD40....

From Nil's Vapor thread...

"I've just started using an excellent protectant called ACF50 on things that I blast. Folks that have been using it swear by it, and it is in fact more expensive per gallon then the airport-grade single malt scotch I drink."

Apparently, it is an anti-corrosion compound....

http://www.acf-50.co.uk/

Ahh, yes, I do remember reading that...

[SOHC4 Cafe Racer Fan]

I have some of that stuff.  I should use it more often.  It looks like it is a decent oxidation/corrosion preventative, as long as it doesn't get displaced.