Does this rephase plan sound too crazy?

[alfredo]

So, I have rebuilt the motor and driven it prob about 2k miles. It was my first bike build and first bike ever really ridden. I must say, it's been a blast and tons of fun. With all of these good times came one repeating problem: vibration. I have done a bunch of things to make this beast ride reliably, but I just can't get over the vibrations.

Enter a new word: rephase. It's what all the cool kids are doing. Snatching up 750 kits from Mikes, sending Hugh some rusty gold and making Pete work weekends to keep up. Chasing the dream of souped-up, vibration free rail riders. I see them . . . . I wanna be in cahoots with them (the cool kids). Now, there is just one problem . .

Enter important word number three: moolah. It just takes too much to achieve this. Without seals and such, I am looking at close to a cool thousand (USD) just for the big bore kit and a pamco kit for the rephase. Adding things like the cost of the crank/cam rephase, seals, gaskets, cam chain, etc . . starts to rain on my dream a little.

So, onto my reason for posting this. I am sure it's been talked about a bit, but wanted to put it out there as a direct question. If I rephase the motor with stock pistons and maybe put in mikes 5th gear, will I just be going 75% of the way 'there'? There being the sweet spot to make my bike a real cruiser. I am looking to be able to ride at 75/85mph for days without vibrating my teeth loose or lose feeling in my hands. I have spent a good amount of time eliminating vibration using the usual methods (timing & tuning) and am ready to go big here with the rephase. I am looking for sewing machine smooth ladies and gentlemen

I just don't want to do all of that work if not including the 750 big bore means I am only half way there. I can wait and save another 8+ months for the big bore kit, but would really like to button this up soon and spend the extra dough on a new 5th gear, some glyptal, a PMA kit and maybe one of those fancy new MLS gaskets. It's just hard to justify the money if the only real difference is the 750 will get me to 85mph faster than the 650 will.

Am I as crazy as this guy?

 

[I am Carbon]

I'm sure your crazy! maybe not as much as that guy .Be it sounds like a good PLAN to me!

 

[Jack]

I'd go the 750 route just for the extra bottom end grunt power and use the Wiseco 750 piston cuz they're heavier in making the 50% balance factor for the rephase

 

[nj1639]

IF you're talking moolah, I'd get some weighted bars, 17/30-18/30 or 18/32 gear ratio and then borrow a gps to see how that works out with vibes, speed and rpm. It would be interesting to see how the overdrive along with those combos affects the vibes. Not sure what your cc's are with the 3rd overbore.

 

[CDNTX650]

to me the whole coolness of these motors is 360* crank...If you wanted smoooooth shoulda chopped a 4 cylinder.

 

[PhatTony]

I too wanted to be one of the cool kids but my moolah was not readily available either. I just rephased the 650. I figured I'd do the bottom end stuff first, ride the crap out of it and then think about the 750 kit. The stocker had enough power for me so I'm not sure if I will ever upgrade.

 

[blackbetty]

Alfredo you're a young man, the vibes help build your character!

If it were me I'd build up a 700cc and skip the rephase HELL YEA, especially for a street chopper.

Or at the very least, stick with stock bore and just bump compression by using thin copper gaskets, or no base gasket at all.

You'd probably be in budget with the engine rebuild incidentals and a touch of performance if you kept the 360* crank.

edit; derp, saw you are running an over bore

 

[AceofSpades]

just curious here... would the 750 kit on a stock crank INCREASE the vibrations? mine shakes like a leaf in a windstorm in pure stock form, and my damned fool ass made it rigid with a solid mounted steel seat... without padding... its great for a bar hopper, but anyting over 55-60 will rattle more than my teeth...

 

[Punkskalar]

There are some cool little speed tricks you can do cheap.

If you have good stock bore pistons, bore and rings, keep em. The big bore is nice, but not required. Delete the base gasket, advance the cam 4 degrees, rephase, add 5th OD and you'll have a great running moto that runs smooth and has great power delivery

I got to ride this bike a while back http://hughshandbuilt.blogspot.com/2011/04/another-rephased-engine-jason-hs-chop.html and it is bone stock internals, with a 5th OD and even running stock carbs. That bike had more than enough power, and was a blast to ride. I could side step the rear tire around a corner, and if the clutch wasn't so tired (he kept the original to save some cash) I think it would pull the front wheel.

 

[retiredgentleman]

alfredo;

If you're looking for a vibration free, high horse power bike, you bought the wrong bike.

Vibration is just part of the charm of these bikes. I ride for 6 hours a day on 2000 km trips and have no problem with vibration. These are 50 HP engines and have enough power for me. Actually at 3400 feet ASL I probably only have 45 HP. I don't ride with guys that have 100 HP bikes.................they drive 40 to 50 kms over the speed limit and I drive at the posted speed limit..............imagine that!

You just spent money on a re-build, and now you want to spend more money on another engine re-build You don't need 750 cc's, rephase or PMA to enjoy these bikes. These bikes achieved their popularity without any of those high priced add ons.
Be aware of all the "marketing" on these sites, which is trying to suck as many dollars as possible out of your pocket.

I say enjoy what you have, or else buy a 4 cylinder silky smooth bike (or maybe a 2 cylinder with a balancer) if you must.

These bikes are a "man's bike"..............those silky smooth bikes are for those who can't handle a "real" bike

 

[1974jh5]

I'm contacting my attorney. Those guys were not supposed to release that vid of me.

 

[Patches]

Alfredo, just keep in mind that you can always do the big bore kit later. No hurry. You've rebuilt these motors before. Top end is cake. Do the rephase, and later you can add the BB if you feel its necessary.

 

[alfredo]

I'm sure your crazy! maybe not as much as that guy .Be it sounds like a good PLAN to me!

hahaha. Nice

IF you're talking moolah, I'd get some weighted bars, 17/30-18/30 or 18/32 gear ratio and then borrow a gps to see how that works out with vibes, speed and rpm. It would be interesting to see how the overdrive along with those combos affects the vibes. Not sure what your cc's are with the 3rd overbore.

I am running 17/32 now and I'm sure I couldn't read the gps screen at 60mph, due to vibration. Weighted bars sounds like a good plan either way though. At least silicone filled or something.

I too wanted to be one of the cool kids but my moolah was not readily available either. I just rephased the 650. I figured I'd do the bottom end stuff first, ride the crap out of it and then think about the 750 kit. The stocker had enough power for me so I'm not sure if I will ever upgrade.

How is it working out for you? Have it on the road? I am curious what you are able to cruise at.

Alfredo you're a young man, the vibes help build your character!

If it were me I'd build up a 700cc and skip the rephase HELL YEA, especially for a street chopper.

Or at the very least, stick with stock bore and just bump compression by using thin copper gaskets, or no base gasket at all.

You'd probably be in budget with the engine rebuild incidentals and a touch of performance if you kept the 360* crank.

edit; derp, saw you are running an over bore

Hahahaha . . . "build your character". I took the bike out once to see just how long I could take it and I made it 4 hours. Had to stop because the vibrations literally had my hands in pain (with padded gloves). Took about an hour and a half nap in a field and then made my way home. Never passed ~60/65mph because I was in fear of my fingernails shaking out.

just curious here... would the 750 kit on a stock crank INCREASE the vibrations? mine shakes like a leaf in a windstorm in pure stock form, and my damned fool ass made it rigid with a solid mounted steel seat... without padding... its great for a bar hopper, but anyting over 55-60 will rattle more than my teeth...

Good question. I would imagine so if the crank and opposition of the pistons is the reason for the vibration, but someone more qualified should jump in on that one. Not to be cruel, but I'm glad someone else experiences the "shake of death". I'm not alone.

There are some cool little speed tricks you can do cheap.

If you have good stock bore pistons, bore and rings, keep em. The big bore is nice, but not required. Delete the base gasket, advance the cam 4 degrees, rephase, add 5th OD and you'll have a great running moto that runs smooth and has great power delivery

I got to ride this bike a while back http://hughshandbuilt.blogspot.com/2011/04/another-rephased-engine-jason-hs-chop.html and it is bone stock internals, with a 5th OD and even running stock carbs. That bike had more than enough power, and was a blast to ride. I could side step the rear tire around a corner, and if the clutch wasn't so tired (he kept the original to save some cash) I think it would pull the front wheel.

Did you advance the cam with a degree wheel or some other trick? Four degrees sounds easy to get wrong for a simpleton like myself. What would you say the vibration reduction is through the power band of a rephased xs? It's not so much that I want a hotrod that is smooth running, but I-95 is 75mph minimum. 85/90 to keep up with traffic and there is lot's of I-95 that I would like to trek.

alfredo;

If you're looking for a vibration free, high horse power bike, you bought the wrong bike.

Vibration is just part of the charm of these bikes. I ride for 6 hours a day on 2000 km trips and have no problem with vibration. These are 50 HP engines and have enough power for me. Actually at 3400 feet ASL I probably only have 45 HP. I don't ride with guys that have 100 HP bikes.................they drive 40 to 50 kms over the speed limit and I drive at the posted speed limit..............imagine that!

You just spent money on a re-build, and now you want to spend more money on another engine re-build You don't need 750 cc's, rephase or PMA to enjoy these bikes. These bikes achieved their popularity without any of those high priced add ons.
Be aware of all the "marketing" on these sites, which is trying to suck as many dollars as possible out of your pocket.

I say enjoy what you have, or else buy a 4 cylinder silky smooth bike (or maybe a 2 cylinder with a balancer) if you must.

These bikes are a "man's bike"..............those silky smooth bikes are for those who can't handle a "real" bike

Don't get me wrong, I really enjoy this bike and would ride it as is if I didn't know any better. I think this thread effectively deflated the "750 kit is awesome" balloon for me. Which is a good thing. I probably won't ever get now. But, with that said . . . I do feel like being aware of the rephase makes me "know better". I am not looking for a drag bike that rides like a chrysler. Just a bike that lets me cruise on the interstates around here (65, 75 mph speed limits) without making my teeth chatter and vision blurry. I can deal with vibration and would probably become used to it over time if I had to, just wouldn't mind spending a few bucks to reduce the vibration substantially. Especially since I just went through the most of the motor. Getting more familiar with the bottom end wouldn't be a bad thing for me either. Also, as for the PMA; I think you are right on that. My charging system works for now so why spend the money when I don't have to?

I'm contacting my attorney. Those guys were not supposed to release that vid of me.

Too funny man!

Alfredo, just keep in mind that you can always do the big bore kit later. No hurry. You've rebuilt these motors before. Top end is cake. Do the rephase, and later you can add the BB if you feel its necessary.

Great advice and exactly what I am going to do now. Thanks amigo!

 

[oldbiker]

hi it sounds good ,,a guy in maffra australia ... rephased his xs650... first over size ,,,,then he moved it 3 splines and put it all back to gether ,,,he built his own electronic ignition set up running off the crank,,, and a set of rear sets to give him room for his set up of his ignition ,,, i took it for a ride around orbost .. and it sounded sweet ,,, like a ducati following me .. i didn,t tell him i nearly dropped it doing a left turn and listening to the sound .. but all ended well regards oldbiker

 

[PhatTony]

How is it working out for you? Have it on the road? I am curious what you are able to cruise at.

I have not. I'm in the assembly stage right now. I was hoping it would go as fast as mock up but it looks like it's gonna be April before I get to run her. I changed my gearing already though. I figured since the rephase will free up some torque it will handle the steeper gearing in town better so I went with 18/31 gearing and I'm running Mikes 5th Gear.
Speaking of vibes, I did have this engine running a year ago on my roller cart with just a strap holding it down. It ran for a good 2-3 mins before I shut it down. Pretty sure a stock motor would have vibrated the cart into pieces in that time. My stock bikes will walk themselves down the driveway on their center stands when revved.

 

[AceofSpades]

Ya know... some of the ladies really like the vibes from an XS..... just sayin

 

[alfredo]

hi it sounds good ,,a guy in maffra australia ... rephased his xs650... first over size ,,,,then he moved it 3 splines and put it all back to gether ,,,he built his own electronic ignition set up running off the crank,,, and a set of rear sets to give him room for his set up of his ignition ,,, i took it for a ride around orbost .. and it sounded sweet ,,, like a ducati following me .. i didn,t tell him i nearly dropped it doing a left turn and listening to the sound .. but all ended well regards oldbiker

Do you remember how the vibes were and riding around australia sounds like a dream I had once. Cheers to you friend from the other half of the world!

My stock bikes will walk themselves down the driveway on their center stands when revved.

hahahahahahahahahahahahahahaha. Made my night with one sentence!

 

[yamaman]

hi, i found after 750ing mine, the sound and vibrations (well they are the same thing i guess) lowered in frequency. the vibes are less tingley, and the exhaust note is much deeper. HP, well its not like going from a Vespa to a R1, you'd probably get more HP by just doing the head. The 270' thing i can certainly vouch for, i have a TRX 850, a modern XS, man that bike is sweet and smooth. I once had a 916 owner tell me my bike sounded more like a Ducati than Ducatis do! Cheers

Posted via Mobile

 

[Revolucien]

So PhatTony, did you just change the cam crank and ignition? I am thinking this might be the route I take as well to knock the price down.

 

[Purplezinger]

I've owned and ridden xs650's for 40 years, "What vibration"?