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Cafe Murdock
Murdock
So let me ask y'all a quick carb jetting question I've got 34mm mikunis with 74.0 big jet and 42.5 small jet I'm running k&n pods and I'm getting ready to put lowbrow customs mufflers on n a couple days I no I need a bigger jet for starting and idle 4 sure but not sure bout the rest any thoughts
Didn't realise that.......may have to be a member to access the Club Racer, although i didn't think that was the case when it came to the club site access for out siders????
Cafe Murdock
Murdock
U no a good place to get bigger Jets for bs34mm carbs im running pods n im I'm bout to put lowbrow mufflers on and i need to go up to 45 on pilot prolly an atleast 1 size on main
niche cycle supply is good for jets, they ship first class with low shipping charges.
Micha7el
XS650 Enthusiast
can you recommend a shop to do a rephase- this is a tic of mine - i love rephased motors...yes this is changing the crank set up so the pistons dont travel together...the advantage is that you dont lose energy when both pistons are at TDC as 1 piston is always mid stroke when the other is TDC..ie rephase-when one piston is not moving (TDC) the other is at max velocity (mid stroke)...removes the search for energy to overcome inertia when both pistons are stopped together (non-rephased TDC)
- so there is a power saving
- this leads also to less vibration as the motor runs smoother
- better responsiveness
- slightly torquier
- if you do this weld the pins to the flywheels...balancing helps too
- there are 2 ways of doing this
- split the crank in the middle-rotate the right hand side 3 splines and press back together...277 rephase
- split the crank, replace the 2nd flywheel from the right with a slightly modified 3rd flywheel (remove 21mm from the pin boss where the cam sprocket seats), use a 270° pin and press together 90° out of phase...270 rephase
- both of these processes require a suitably modified camshaft and a cam-driven ignition system...a good time to consider installing a permanant magnet alternator and dual lobe points cam
- in my opinion yamaha missed a golden opportunity to produce a truly extraordinary motor by turning this idea down...i have done this and highly recommend this to anyone interested in spending the effort...virtually all modern-day parallel twins are built this way
burns
OWG
lets cut the bs. rephasing reduces vibration that is its ONLY advantage. the net résistance is EXACTLY the same as stock and there is ZERO increase in torque. If you want a little more torque with the same cc go with the original design rod /piston, if you want a lot more, Wiseco sells cc's
The paint can shaker motor is part of the personality of the bike; get a W650/800 if you want a jap psuedo retro BRIT with nicer manners; its your money but IMHO it would be better spent with that choice.
The paint can shaker motor is part of the personality of the bike; get a W650/800 if you want a jap psuedo retro BRIT with nicer manners; its your money but IMHO it would be better spent with that choice.
member3480
RICH
Here is the good side and the bad. Changing the crank ratio will stop some of the vibration at top end. Does it increase horse power no. Some people like it because they ride bikes on highway and the vibration is not as bad as the teeth shaking on stock. Now the bad side break down or not done correctly. Both are weeks or months to repair not days. What I mean is if your crank or cam have a problem stock you can jump on here or eBay and get another and in days fix it. If your rephrase cam or crank have a problem you may have to buy a new one from who you got the first one from or wait weeks to get it back from repair. I have used both and I now just use stock crank and cam on my builds.
member3480
RICH
Your bike your build just my opinion.
you're asking a question to a 11 year old post
the only ignition available in the us that I know of would be a points modified base plateor order an electronic ignition from Heiden tuning. Hoss Racing or Hughs Hand Built
Rephasing will move the harshest vibration but it won't eliminate it; you'll still have a two cylinder motor without a counterbalancer on the crank. If you want a smoother motor, spend your money on the basics: have the rods and pistons beam balanced and true the crank. Mama Yama's crank production was not a class act. Yamaha allows .002" as max runout measured at the journals, and if you've had a few on the V-blocks you'll know how many of these cranks fall outside even that sloppy spec.
Steve C
XS650 Addict
I would recommend working with Gary Hoos at Hoos racing, handle on here is Hooser http://www.xs650.com/members/hooser.12299/you're asking a question to a 11 year old post
or order an electronic ignition from Heiden tuning. Hoss Racing or Hughs Hand Built
He also supplied me with a Vape (formerly Powerdynamo) 277 crank mounted ignition and PMA and a megacycle 250-20 277 cam. He has been awesome to work with and super responsive whenever I've had questions
As for whether to do it? Depends on what you can afford and what you will use the bike for.
There are clearly 2 camps on here. Purists who think the best parts and configuration were produced by Yamaha and should be left alone in service of stock reliability and ease of repair/finding good used parts. If this was going to be my daily rider or a bike I picked up that ran just fine to begin with, I would be more inclined to leave it alone and ride as-is.
Then there are those who are into coloring outside the lines a little bit and willing to try this different configuration and some aftermarket parts. My motor was DOA when I got it so did some reading and the rephrase made sense. I like the sound and feel of a 90* v twin and I want to use this bike for long summer trips and don't want to feel like I've been sitting on a paint shaker all day. More power, probably (purists would say definitely) not, but in my mind vibration is wasted energy and additional load on critical parts. If vibration is reduced running at higher RPMs, in the higher gears, stands to reason these critical parts will subjected to less stress.
Don't know for sure...have not seen any apples to apples durability tests head to head stock vs rephrase...
Grain of salt, JMHO.
You will get strong opinions on both sides. Like Daddygcycles said above, Your bike, your build!
Good luck.
Uh, make that three camps, Steve. Right out of the crate, some of these mills were as smooth as a motor gets without a counterbalanced crank, and others would shake the fillings out of your teeth--good parts, but often badly assembled and in need of corrective attention. I don't much like the stock rods, either. I've taken down a lot of XS650 motors, and the coating was all or mostly gone from the small end of almost every rod (the Japanese rods Mike's XS used to and may still sell at a decent price are made from harder material and don't need coating, and Wiseco Hot Rods are also decently priced). For the tinkerer, one of the attractions of the XS650 is that there's so very much room for improvement!
burns
OWG
this comment addresses a slightly different question which is basically whether it is wiser to perfect the original design or make significant alterations to it, blueprinting would be beneficial whether you rephased or not.
While no one can argue with "its your build" it is not a bad idea to get a sense of what you are going to get and what it will cost when you plan that build. The fact that there are so many rephasers out there is proof enough that the change is desirable and deemed cost effect to many people. The same can be said of hard-tail conversions. Neither meet my personal criteria.
My basic point is that moving the crank halves a couple splines will not turn a xs650 into a sv650. The xs650 is a Route 66 bike not an interstate mile-muncher. I rode an xs1 from Austin Texas to Lake Placid NY and back and enjoyed every mile cruising at 65 mph and loving the sound and the feel of the bike when I whacked the throttle to pass on the two lane roads I traveled. That is the personality of this motorcycle. Your money is better spent on a different motorcycle if you prefer a different personality
IMHO. But it is your build.
member3480
RICH
The XS650 was never sold as anything but a good reliable bike . I have spend more money on trying to get more horse power out of one with big bores , better cranks, more compression, ported heads , even putting a turbo on one and in the end I just like the way the stock bike runs. I started with Triumph BSA and Norton’s so the vibrations never bothered me because it was just a cool bike to build. I just finished number 54 and have number 55 and 56 on the table. I am not known for building stock bikes but I have done a couple. I have builds all over the USA and two overseas. These bikes are a great dirt track bike and there are many builders of those. Again it’s your bike build it the way you want it but like I tell everyone you want to go fast buy another bike if not just join us at 65mph and have fun.
The biggest fault I have with rephasing and I have been around a few of them is they sound like crap ,they need a particular muffler for a decent
sounding exhaust note. With a XS 360 firing order you can slap just about any style muffler on and it'll still belch out that distinctive 360 twin exhaust
note I grew up listening to.
sounding exhaust note. With a XS 360 firing order you can slap just about any style muffler on and it'll still belch out that distinctive 360 twin exhaust
note I grew up listening to.
burns
OWG
Pea Shooter mufflers on this bike are musical instruments
Ratranger the Torque reading looks pretty sad.
It had severe blow by on the right cylinder due to a wrist pin circlip failing on the dyno. It wasn't fully tuned because of that, acceleration enrichment never got tuned so it would bog if you went wide open too early. So right now it's waiting on me to get a house so that I can go 700cc big bore and retune.
