Topic: Re: 650 overbore/550 engine hybrid underway...final stages

[MRieck]

i would just like to say that brand new NOS crank, rod, and trans bearings, rod nuts and bolts, seals, chains, circlips, etc. are:

1) such a beautiful thing.
2) such an expensive thing
3) the last stuff i was waiting for to put this engine together!

 

Nows the good part Paul.

[paulages]

i would just like to say that brand new NOS crank, rod, and trans bearings, rod nuts and bolts, seals, chains, circlips, etc. are:

1) such a beautiful thing.
2) such an expensive thing
3) the last stuff i was waiting for to put this engine together!

 

Nows the good part Paul.

yeah, can't wait. i'm headed out of town for a couple weeks. by the time i get back, my cam should have arrived from megacycle. 

[erb4]

Paul,

Any updates?!?  The anticipation is killing me!


Ed

[paulages]

Paul,

Any updates?!?  The anticipation is killing me!


Ed

well, i did return home,  but the cam hasn't, nor have the 4 black bearing shells arrived from DSS that i need to put the bottom end together at least. i thought i had all of them, but servicehonda made a mistake and i had to source them elsewhere. get ready for more anticipation, because i leave town again for tour on thursday, and won't be back for another 10 days. believe me, it's killing me to not be able to throw this thing together...

[bill440cars]

Paul,

Any updates?!?  The anticipation is killing me!


Ed

well, i did return home,  but the cam hasn't, nor have the 4 black bearing shells arrived from DSS that i need to put the bottom end together at least. i thought i had all of them, but servicehonda made a mistake and i had to source them elsewhere. get ready for more anticipation, because i leave town again for tour on thursday, and won't be back for another 10 days. believe me, it's killing me to not be able to throw this thing together...

          I can well imagine, I'd be the same way.

[erb4]

well, i did return home,  but the cam hasn't, nor have the 4 black bearing shells arrived from DSS that i need to put the bottom end together at least. i thought i had all of them, but servicehonda made a mistake and i had to source them elsewhere. get ready for more anticipation, because i leave town again for tour on thursday, and won't be back for another 10 days. believe me, it's killing me to not be able to throw this thing together...

If one were to start with a 650 engine, would it be a simple matter of installing the 836cc CB750 pistons and liners, plus the machine work to get the liners in?  Why did you start with a 550 engine instead of basing your build on the 650 bottom end?


Thanks,
Ed

[scunny]

I could be wrong and often am ... he wants to have a kick start

[paulages]

I could be wrong and often am ... he wants to have a kick start

bingo. i'd rather have a kick and no electric start than the other way around, any day of the week. when i have a functional electric starter i seldom use the kicker at all, but it sure sucks to have a low battery and bumping as the only means of starting...not to mention the fact that the kickstart shaft and lever are much lighter than the starter motor. plus, my bike is a cb550-- i liked the idea of overboring a 550 engine, even if it ends up only being the cases, primary shaft, kickstart shaft, and 1st gear that are actually from it. 

[paulages]

lookie what i got today. 

[MRieck]

lookie what i got today. 

What's it doing on the bench Paul?? Throw it in there boy!

[paulages]

lookie what i got today. 

What's it doing on the bench Paul?? Throw it in there boy!

that's not my bench, that's my kitchen table! 

as long as they can take, surely DSS will have my last 4 bearing shells at my doorstep in the next 10 days. then, it will find it's cozy home. 

[MRieck]

 OK....I'll accept that answer.....for now.

[bill440cars]

lookie what i got today. 

          ALRIGHT PAUL! ThatIS one FINE looking camshaft!

           Seems like I remember the discussion about having a "kicker" on that motor, back in the beginning of this, and I've got those occasional "Senior Moments".                      

[erb4]

Paul,

What if someone wanted to take the easy way out?  What would it take to build a 718cc engine from a 650cc core?


Thanks,
Ed

I could be wrong and often am ... he wants to have a kick start

bingo. i'd rather have a kick and no electric start than the other way around, any day of the week. when i have a functional electric starter i seldom use the kicker at all, but it sure sucks to have a low battery and bumping as the only means of starting...not to mention the fact that the kickstart shaft and lever are much lighter than the starter motor. plus, my bike is a cb550-- i liked the idea of overboring a 550 engine, even if it ends up only being the cases, primary shaft, kickstart shaft, and 1st gear that are actually from it. 

[hymodyne]

lookie what i got today. 

          ALRIGHT PAUL! ThatIS one FINE looking camshaft!

           Seems like I remember the discussion about having a "kicker" on that motor, back in the beginning of this, and I've got those occasional "Senior Moments".                      

[hymodyne]

Can someone give me the settings on the two pages shown with the cam? I'm putting a 650 cam in a 500. Will my settings be similar to those listed with the cam pictured?

hym

[paulages]

hymo- i can when i get back.

erb- all the info is there if you read through the thread, but i guess there is a lot to read through. you'd have to press out the sleeves and bore the cylinders to fit the 750 sleeves, which must be shortened and tapered to fit in the 650 cases. you'd be hard pressed to find pistons that won't require machining as well. i can provide fairly accurate mod specs on the specific pistons i used, but other than that you have to go through the same process i did to dial in the clearances.

[hymodyne]

Hey there Bryanj,

Can the 650 head gasket be used on a 550K head?

hym

[paulages]

Hey there Bryanj,

Can the 650 head gasket be used on a 550K head?

hym

in case bryan doesn't answer you- the stud pattern is the same, it's just that the cylinder holes and fire rings will be bigger. i don't see why you would unless you were using 650 pistons.

[Soos]

Do the 650 cylinders have the same center to center pattern as the 500/550 motors?

I beleive he is tring to find an alternative gasket for a 605cc overbore kit, without having to go through cometic for one.
(61mm? pistons for a 605 overbore kit)

l8r

[paulages]

Do the 650 cylinders have the same center to center pattern as the 500/550 motors?
l8r

yes. i'll have a look at both as soon as i get back in town and check to see if the opening for the tensioner is compatible. i know the base gasket is different in this regard.

[FunJimmy]

Paul

Thanks for all your hard work providing such valuable research into the 550/650 hybrid engine. I’m looking to build a hotter 550 engine and have found some 61mm forged pistons from a Honda GY6 engine. What I know is these pistons are 61mm forged flat top, slipper style pistons with 15mm wrist pins. The pin to deck height is advertised to be 13mm, but that may not be center to top. If not, add 7.5mm for 20.5mm, considerably less than the 23mm that the 550 pistons have.

I thought that a 650 crank with its longer stroke combined with rods from either a 550, 650 might be combined to adjust the difference in pin to deck height, giving a displacement of 652cc.

Alternatively could I use the 650 crank and rods with my 555 59mm piston for 610cc.

My question is…will the 650 crank bolt into the 550 cases without any further modifications other than boring out the 550 stator?
If so can you have your machinist bore out my stator?
Can I use the 650 Hyvo cam chain with my 550 cam providing I get a 650 cam sprocket?
Are there any other obvious concerns that you see?

Thanks for all your help.
Jimmy

[genejohnson]

If the outside cylinders are offset by 1 mm, how does that affect the crank/rod lining up with the cylinder? Gene

[Soos]

If the outside cylinders are offset by 1 mm, how does that affect the crank/rod lining up with the cylinder? Gene

Did I understand paulages wrong? I thought he said they were the same

[paulages]

i don't know where somebody got the 1mm offset thing, unless it was in reference to thayes wrote about what someone else was doing with some kawa pistons.