701 Conversion- How To.

[The other Alex]

What does it take to convert from a 6m6 motor to a 701?
650 Crank, all I would need is 61X cases and 61X head? Do the pistons stay the same or would you need new pistons?
Just want to keep my eye out over the winter...

 

[The Penguin]

keep the crank and electrics

you'll need cases, cylinder, head, intake, carbs, pipe

I think I got it all

 

[Rickster]

From what I have read and been told, there is little difference between 6m6 and 61x cases, so clearance the 6m6 cases to fit 61x jugs, and wallah! 701cc's:arms:

 

[Mouthfulloflake]

From what I have read and been told, there is little difference between 6m6 and 61x cases, so clearance the 6m6 cases to fit 61x jugs, and wallah! 701cc's:arms:

the 61x reeds and cages are quite a bit larger.

I woudl assume that a stock 701 cylinder would work with a set of 6m6 cases.

but for a ported 701 or larger, I would go with the 61x cases, OR the 62t cases.

 

[romack991]

carb is the same. (44)
intake/reeds
top half of case
cylinder
exhaust
pistons (unless 650 was already bored out to 81mm)
head - i will hook you up with one free if you want it.

 

[The Penguin]

I think for the cost of clearancing 6m6 cases - you could find a set of 61X or 62T cases for just a bit more and get the advantage of the larger intakes they provide.

afterall - what good is a Ferrarri if you put a Yugo carberateur on it?

 

[Rickster]

the 61x reeds and cages are quite a bit larger.

I woudl assume that a stock 701 cylinder would work with a set of 6m6 cases.

but for a ported 701 or larger, I would go with the 61x cases, OR the 62t cases.

Trust me, there is little differenece.

I run a ported 701 on 6m6 cases with 185 compression, and I honestly could not justify the expense of converting to a 61x, especially with the little gain in power. (compared to other 61x SN I have ridden)

Now saying that, I do have a 62t engine in my garage that will be going into my RN, and I also have 62t cases on it's way to replace that 6m6....:biggrin: :Banane01: :biggthumpup:

 

[Mouthfulloflake]

Trust me, there is little differenece.

I run a ported 701 on 6m6 cases with 185 compression, and I honestly could not justify the expense of converting to a 61x, especially with the little gain in power. (compared to other 61x SN I have ridden)

Now saying that, I do have a 62t engine in my garage that will be going into my RN, and I also have 62t cases on it's way to replace that 6m6....:biggrin: :Banane01: :biggthumpup:

is the 701 cylinder on the 6m6 cases ported? or stock?

I wonder why the factory would bother to engineer a new set of cases, AND increase the HP numbers at the same time?

IM sure the 6m6 will work, the 61x is better, and the 62T likely better still.

 

[DaUpJetSkier]

the ideal combo is 62T top and bottom case and 61x cylinder right? But if you did put a 61x on 6m6 cases is it the same thing you would have to do if you were to put a 550 jog on a 440 bottom end? Just bore it out so the piston skirt fits through.

 

[Rickster]

is the 701 cylinder on the 6m6 cases ported? or stock?

Ported with a b-pipe...:woot:

Just a thought to keep his prices down and get the increase he wants.

I would rather see him pay $200 for a 61x topend and then have some money to port the cylinders (that can always be used on a 61x or 62t later on) than buy the cases, jugs, reeds, exhaust etc. for a minor step up.:biggthumpup:

 

[The Penguin]

keep an eye out for 62T cases though - a set came up here not too long ago for $200 and they were clean :wink:

 

[Rickster]

keep an eye out for 62T cases though - a set came up here not too long ago for $200 and they were clean :wink:

I know, I bought them along with the B-Pipe...:biggrin:

 

[The Penguin]

you got the b-pipe from yesterday?

butthead!

 

[Rickster]

Mr. Butthead to you Sir....:woot:

I needed something for my RN.

 

[The Penguin]

allrighty then "Mr. Butthead"

I need a B Mod pipe deal like that one

you gotta keep an eye out for me

(please?)

 

[Rickster]

Deal, but if I find it, you have to take it...:biggthumpup:

My wife would kill me if I bought another.....:frown:

 

[The Penguin]

thanks!

 

[Mouthfulloflake]

I hear ya on the cost, not worth messing with unless the 61x cases were really cheap.

I agree with you, spend it on the cylinder and port job, and then you can move that set up case to case.

that gives me some ideas for the slew of 650s ive got hanging around too.

At what CC do you think the 6m6 cases are erally a hinderance?

how about a freestyle ported 83mm bore?

Ported with a b-pipe...:woot:

Just a thought to keep his prices down and get the increase he wants.

I would rather see him pay $200 for a 61x topend and then have some money to port the cylinders (that can always be used on a 61x or 62t later on) than buy the cases, jugs, reeds, exhaust etc. for a minor step up.:biggthumpup:

 

[Rickster]

At what CC do you think the 6m6 cases are erally a hinderance?

how about a freestyle ported 83mm bore?

I personally think 83mm would be suffocated by the 6m6 cases, and needs to be on 62T's.

Stock bore 61x cylinders on 6m6 cases, with porting and a shaved head, running at 185 psi has ample power at a fraction of the cost.

The move from 6m6 to 61x's just does not make sense to me, when you can pretty much spend the same money and have a 62T with more options.

:dunno:

 

[Matt_E]

carb is the same. (44)

I remember reading on this board that the 650 carb has different internal circuitry.