Topic: Right! That's it, I've had enough! - Fancy engines question.

[CrisPDuk]

That's it. I'm fed up of reading about you guys and your over-bored this, your ported that, and your megacycle the other Whilst I'm here with my stock little 550K

So I've decided it's time for me to take affirmative action, and I'm opening the floor to suggestions

I've got a totally stock '78 550K, still running sweetly with 40k miles under it's belt. What are my options?

A new, bigger set of pistons would be nice, with a camshaft, and maybe rods if really necessary, and a decent porting job would appear to be essential. Bearing in mind that the bike is resident in the north west of England, my question is who is the man for the job?

Bear in mind, I want road driveability, not a drag racer

[medic09]

Leave the sweet bike stock, and get a Maserati for those other 'fits of passion'.   

[heffay]

oooooh... maserati... pops had a biturbo spider a few years back.  it was dubbed the poor man's maserati.  wicked fast, it would leave my SHO in the dust.  i think he only plunked about 8-10k for that one.

but, cris... it sounds to me like you want a drag racer and have the driveability.

[CrisPDuk]

Since I already 550+bhp spread over my 3 cars (one of which is still packing the stock 110 ) I think my four wheeled accelerative needs are pretty much sated Doc   Never say never though

What I'm feeling the need for now is more, and quicker, bugs in my teeth


Hmmm, a driveable dragster, there's a thought. Thanks Heff

[cafe75-550]

I would look into the 605cc overbore kits by Henry Abe, see them on ebay. They're listed for 500's, but will work for a 550 without the sleeves. This would give you a 592 (how that works out to 605 I don't know) and has all the goodies you need. The rings are odd, so if you needed to replace them it might cause some problems...

See here http://cgi.ebay.com/ebaymotors/Honda-CB500-Four-BIG-BORE-605cc-Performance-Rebuild-Kit_W0QQitemZ220077042425QQihZ012QQcategoryZ35595QQrdZ1QQssPageNameZWD1VQQcmdZViewItem

That with a megacycle cam and some porting would really wake the old girl up, but would still just entail a bore and the kit includes everything you need. Since it doesn't entail a lot of custom work (just the overbore and pistons) you should still have a very streetable bike.  You shouldn't have to worry about the bottom end other than perhaps new bearings if needed, and I really haven't seen anything in the way of rods for the 550's...

[Sam Green Racing]

Sounds like crispy duck is having a go at a nice person that offered to have a drink with him

I think I will have to contact my soliciter

Sam.

[CrisPDuk]

I'd say more a gentle placing of gauntlet myself Sam I hope it hasn't caused you to recind the beer offer


Do you fancy the challenge yourself then



And what's this talk of solicitors then   What's wrong with good old fashioned handbags at dawn

[Jerry Rxman Griffin aka MuthaF'er]

My philosophy is leave them stock until you HAVE to open them up -OR- why open them up and not make them better

[TwoTired]

I say leave the 550 street sweety engine alone.  But, yank it and drop a 650 in its place.  When you get tired of wrenchin' on that, and just want a sweet drive through the countryside, put, Mr sweety back into the bike.  You may find the grin is now large enough to accept bugs.

Cheers,

[crazypj]

Get it ported, nothing radical just cleaned up and K&N's.
With right jetting its nice to ride, and better of fuel than stock bike (mine went from around 26mpg to 41mpg, including 591kit)
The 605 is only 591 and you can bore stock block to take modified CB750 pistons.
I did over 70,000 miles on mine after the mods, so reliability isn't an issue ( see avatar )
PJ

[DammitDan]

I would leave the stock bike as it is and buy something new (by new I mean old  ) for your stable.  As soon as you start wrenching on that "little" 550, you're gonna wanna be riding it.  And as soon as you start wanting to ride it, you start taking shortcuts and leaving things out to get back on the road.  It's better to have something to ride while you have something to work on, and if you're wanting power, go for a 750 (or a '79 650 if you're strapped for cash... the pre-80s CB650 is the only one without a dropped seat bucket) to wrench on.

Trust me, you'll be happier in the long run when you have a bulletproof (and somewhat bland but more comfortable) stock 550 and a bulletproof (and more exciting but less comfortable) cafe'd 750, as opposed to just a "maybe it will make it but I'm not sure cause I got impatient during the rebuild" 550 

[Terry in Australia]

Nothing beats cubes Crispy, so buy a 750 for when you want to go fast, and keep that 550 for commuting duties, those English streets are pretty narrow!

[CrisPDuk]

Thank's for the replies guys. There's no chance of yu talking me out of this one though I'm afraid. There will be no danger of impatience making me rush the job, because:

a/ I won't be doing it, one I don't have the time, and two, it's alien technology to me, I don't want to screw it up

b/ I'm currently living 8,000 miles from my CB, and in theory will be doing whilst the motor gets built, so I couldn't ride it even if I wanted to and,

c/ When I get back the going proper quick duties will be adopted by a little something that starts with a 'D' and ends in 'aytona'


The reason I went for the 550 and not the 750 was because I prefer it's overall proportions, and the way the engine looks in the frame I just want it to be a bit more spritely that's all


PS: Don't tell MrsD about the Triumph thing, she hasn't had the news broken to her yet

[Terry in Australia]

The reason I went for the 550 and not the 750 was because I'm really afraid of fast bikes, so I tell everyone that I prefer it's overall proportions, and the way the engine looks in the frame I just don't want to get hurt, that's all

Fair enough mate. 

[DammitDan]

ROFL 

[CrisPDuk]

The reason I went for the 550 and not the 750 was because I'm really afraid of fast bikes, so I tell everyone that I prefer it's overall proportions, and the way the engine looks in the frame I just don't want to get hurt, that's all

Fair enough mate. 

 

Laugh? I nearly did





 

[Jonesy]

Check out HondaMan's 550 mods in the FAQ. He lists things that can be done both outside and inside the engine...

[RRRToolSolutions]

Chris,

I find the CB500/550 Four to be my absolute favorite bike to ride. I've ridden hundreds of bikes in my 48 years and have restored several different models as part of my hobby in recent years. The 500/55- Fours just have a balance about them, a riding position, and "perfect" blend of handling that I find most satisfying.

As such, I think your choice to go for more power is a great idea. I like the way the 500's cylinders sit-up straight and the head cover area far more than the 750's. I had a very close friend that has his 550 bored out to 600+ (I can't remember, but it was a popular big-bore kit), added a nice cam, bigger carbs, K&N's, and a 4/1 pipe (I think RC). The bike sounded awesome! It might have been ported, but I doubt it. That bike would wheelie, it would do burn-outs, and Gary could make it fly. I'll never forget him laying it over in tight left-hand curves while dragging his left hand on the pavement. The bike handled so well that he could make curves 1-handed.

With the smaller Four's higher rpm capacity (10,000+), good porting (very, very important), good cam, and some other real, sound choices - you should have a bike that keeps it's low speed manners and sound like a Maserati. The high-reving Fours with a 4/1 pipe sound so awesome. I think it's a gret project and one I'd like to see happen.

Regards,
Gordon

[vintage_racer]

Well,
I race a CB550 with a vintage racing club here in Ontario.
I use stock bore with high compression Yosh pistons, a regrind camshaft, CB750 carbs with K&Ns, HD valve springs with aloy retainers and some porting on the intake side.
Just big bore pistons as available on e-bay wouldn't do much for top HP though you may have more tork at low RPM.
High compression is the way to go together with longer doration cams.
mind you, you can't just drop a hot cam (unless its a mild one) and stay with flat top pistons (your valves will hit the piston top).

There are no high compression pistons available, the only way to go is to modify CB750 pistons (I belive from a F1 not a K).

What you want is a 10.5 compression and a megacycle cam with CB750 carbs, such a bike will run with any CB750.

Dan

[TwoTired]

Hey Dan,
Can I ask how your primary chains hold up to the added power/RPM?
Thanks,

[paulages]

Hey Dan,
Can I ask how your primary chains hold up to the added power/RPM?
Thanks,

yeah, that's question i'd like answered, as i'll be adding almost 200cc's to my 550...

[Jonesy]

Doesn't the 550 use a BorgWarner Hy-Vo chain for the primary? These are extremely strong chains (The guys sooping up CB750's would harvest them out of the A model as they were stronger than the doubled roller chains found in the K and F models)...

I figure if they can use them in transversely-mounted automatic transmissions to transmit engine torque, they should be able to work.

(Sorry, another Dan answering... )

[paulages]

yes they do, and mine will have a hy-vo can chain as well.

[vintage_racer]

After 3 seasons (4-5 race weekend each season) the primary chain is still in a great shape.
Mind you, what's tough on a chain is added torque not added HP through higher revs.
My CB550 probably doesn't have much more torque than a stock 550, but it can breath freelly at 11000 RPM.
I don't have any power below 6500 RPM and the motor comes into live at around 9000 RPM. It's kind of a poor man's R6.

Dan

[paulages]

dan-- pictures? which 750 carbs are you running? i'm trying to decide between 650 carbs or 750 pd carbs for my 718. not quite sure where to start with the jetting, but i imagine the former to be too little and the latter too much. you're getting 11,000 freely with HD valve springs? gives me hope...