Rephasing, What is it?

hi guys ,,,yes,,, boyer do maker an electronic ignition for a rephased motor.... he actually has them listed on his new web site ... and i think he,s in cal... regards oldbiker
 
There is no "Supposedly" about it. While a stock bike will make your hands and feet numb and try to walk backwards down the driveway while idling, the Re-Phase is smooth as silk. :laugh:

Higher RPMS can be reached, smoother running engine won't slosh the fuel around in the carbs as bad at High RPM, etc.. There is definitely more power. My next engine is going to be a bone stock 650 just rephased so I can test it against a stocker...

There is NO requirement for an Early Head to be rephased, just need the Points Rod and Advance unit, and a Pamcopete Ignition.
 
Maybe you gotta chop the bike before standard phase makes you numb all over....
 
Another newby here Hugh. I've got a 73 that I'm building and it's definatly a 256 motor. Does the method of rotating the right flywheel 3 splines and reworking the cam to go 277 rephase still apply here? Can you grind these cams to 277?
 
Another newby here Hugh. I've got a 73 that I'm building and it's definatly a 256 motor. Does the method of rotating the right flywheel 3 splines and reworking the cam to go 277 rephase still apply here? Can you grind these cams to 277?

The 256 cranks cannot be rephased. I can build the cam for you just fine, but the crank will have to be replaced with a 477, you'll need 477 pistons to match, as well as all the timing chain, tensioners, and chain guides. If you have a 6 bolt tensioner on the cylinder head, then you can do the swap.
 
I plan on rephasing my 72'. Anyone know if I can stick any 447 crank and rod assembley in the 72. I was also thinking of doing the 750 kit that mikes xs has with the bigger block. Still wanting to use my 72 head and cam. I guess I will have to have a 447 style cam gear and a new chain and tenioner. What electronic ignition and coils do you guys suggest? carbs? and would all of these parts mesh in my 72 cases? pm me if these are questions you are willing to answer and don't feel like telling the world.
 
I plan on rephasing my 72'. Anyone know if I can stick any 447 crank and rod assembley in the 72. I was also thinking of doing the 750 kit that mikes xs has with the bigger block. Still wanting to use my 72 head and cam. I guess I will have to have a 447 style cam gear and a new chain and tenioner. What electronic ignition and coils do you guys suggest? carbs? and would all of these parts mesh in my 72 cases? pm me if these are questions you are willing to answer and don't feel like telling the world.

Yes.... You pretty much have it figured out. You'll need the 447 Cranks and Rods, which will work well with the MikesXS 750 Kit. You can use the 256 Cam, you'll just need to change the cam gear to one off of a later cam (PM me if you need one, I have several). Change the camchain, guides and tensioner and you are set.

You can use Pamcopetes Ignition, he builds one for a 277 Rephase. You can run stock carbs, or anything that is known to work well with an XS650.

Hugh
 
Hugh, this may be a bit overbored. But what do you think would happen if the bottom end was balanced and polished. I wish we had a cam grind that would chop like a Andrews B grind.
 
hi guys,,, theres quite a few guys in the yamaha xs650 club of australia,, that have rephased their motors,,the guys that seperate and weld it /balance it..and i,ve ridden 1 ,like this method ,,,, it sounds like a ducati which is niceeeeeee.... they nearly all recton that with direct pull carbys and cam ,they are getting up to 40%more torque at the back wheel,,, the guy from maffra ..i rode his yellow rephased home made crank set up ..moved 3 splines.. along with a home made electronic ignitionand that sounded lovely and heaps of grunt his yellow xs650 is on the australian web site.... and the ex club president is an old hand at rephasing/caming/chopping /and playing with different carby set ups mostly direct pull .. thos guys will all help you with info as well ... hope this helps you regards oldbiker
 
At certain revs and 2nd or 3rd gear while accelerating out of a corner I can hear/feel my clutch protesting so I believe there is a significant increase in torque. My advice for anyone building a rephase with the above recipe (750 kit, cam, electronic ignition, direct pull carbs etc.) is to make sure your bottom end is in top condition and your clutch is rebuilt using kevlar discs.

I.
 
At certain revs and 2nd or 3rd gear while accelerating out of a corner I can hear/feel my clutch protesting so I believe there is a significant increase in torque. My advice for anyone building a rephase with the above recipe (750 kit, cam, electronic ignition, direct pull carbs etc.) is to make sure your bottom end is in top condition and your clutch is rebuilt using kevlar discs.

I.

Agreed,

With the 707CC Wiseco Pistons, Ported Head, Oversize Valve, and High-Velocity Lectron carbs I run, the clutch didn't stand a chance. Even with MikesXS "Hi Performance" springs and disks, I still slip and chatter a bit when really dogging on the engine.. Looking to machine the clutch basket and add 2 more disks.
 
There are no power advantages when rephasing,other than power distribution,period! The only thing that changes is the firing order and better utilization of torque that would of been spent pushing double the mass weight on the power stroke of a 360 firing order.
 
There are no power advantages when rephasing,other than power distribution,period! The only thing that changes is the firing order and better utilization of torque that would of been spent pushing double the mass weight on the power stroke of a 360 firing order.

Jack,

I fully respect you, but I have to disagree. I don't have numbers or Dyno figures to back it up, and admit that. But Nobody has ridden around a rephased engine and thought it had the same power of a stock engine that I know of. And, to try and prove the Rephase builds more power, I am building a bone stock engine internally, all stock pistons, cam, etc... just rephased and will be testing it in a known chassis. :thumbsup: Hopefully that will happen this spring. I will find someone willing to dyno their bike, and GIVE THEM A FREE REPHASED ENGINE if they will do a before and after dyno test... :D

If I am proven wrong, I'll be happy to admit it. But the rephases just keep proving to be a powerful engine with excellent throttle response and torque. Even a 750 Kitted XS isn't comparable to a rephased engine, in my personal experience.
 
Punk basically implies what I was going to say which is that very few people have the rephase and leave the rest untouched, most seem to have at least the carbs upgraded, and a good number, since the engine is in pieces, put on a 750 kit.

I'm also a bit biased as I bought my bike with all the mods done by the PO so have no way of comparison with a standard bike, but would still like to dyno mine. I do like that I can be at 40mph in 5th and just roll on the throttle will get me up to 60mph in a few seconds.

I.
 
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