Is my Rephased crank a righty or a lefty?

adi1974

XS650 Addict
Messages
145
Reaction score
0
Points
16
Location
Devon, UK
Hi guys, my crank was rephrased by a local (at the time) moto engineer a couple of years ago. I asked him to do a right side advance same as most people seem to do. He was going to do a matching cam for me but ended up saying (after having the cam and crank a year) that he was unfortunately too busy to do it and so I've been looking elsewhere for a cam.

I have now found someone who can but they asked if I can confirm if I know "which side fires first" on my set up. I said I think its a RHS advance and they said that should mean its a LHS fire first RHS second. I've no idea if thats right or not. How can I ensure how mine is set up by looking at it? As far as I can tell it is indeed RHS advanced but I'm not sure and certainly not sure what that does for the firing order. Any advice please?

Also I'm now worried about the crank sprocket and whether or not that's been put back on in the right place to match up with the cam timing Again, is there any way of checking? I can post photos if that helps. The uncertainty is killing me. hah

Cheers - adi

xs650_277.jpg
 
just blathering til someone who knows comes along, but I'm with you looks like the RH side is first. I'll also guess it means the LH side fires then 277 degrees later the RH side fires. Crank sprocket is fixed, cam sprocket can be pressed in any location for timing.
 
I agree with Gary, that is precisely what my crank looked like when rephased. What method will you use on the cam? I am in the process of doing a second motor, #2 son's motor performs excellent.
 
I suppose a simple way of looking at is that the right crank is 83° advanced from the left, so the right half of the cam should be advanced half of that (41.5°) to match it...
 
Thanks for the replies. I'd like to know if there's a way I can 'know' for certain rather than guessing?

I dont really know about the firing order still. Does right side advance on the crank mean its a left side fires first? My brain can't work that out. :wink2: I don't really want to commit to saying yes or no on a guess.

I've seen that the crankshaft sprocket is removable so would also like to know if I can check this position as my cranks were stripped, no idea if they removed the sprocket or not.

I'm not sure what method is being used to do the cam but its being done by a reputable, well known place, its just that there's a bit of a language barrier which makes explanations tricky. They asked me to check stuff but couldn't give an explanation of how to do so. Just want to be sure for peace of mind. - Thanks again!
 
The left side of the crank is essentially left unchanged to keep the timing marks the same. So in your case the left side will fire and then 277* later the right side will fire assuming that the left cylinder reaches the correct ignition timing range on the compression stroke first. Talk to Hugh from HHB he very well may be able to do your cam and do it correctly just by looking at the pics of your crank.
 
Thanks. I've spoken to Hugh, but he said he was too busy to assist with my cam so I've gone elsewhere. My cranks were stripped and all bearings replaced so I'm not 100% sure the left side is unchanged. Thats the kinda thing I wish I knew how to check so I can be sure its put back together correctly to match a potential cam.
 
Thanks. I've spoken to Hugh, but he said he was too busy to assist with my cam so I've gone elsewhere. My cranks were stripped and all bearings replaced so I'm not 100% sure the left side is unchanged. Thats the kinda thing I wish I knew how to check so I can be sure its put back together correctly to match a potential cam.

I surely am not too busy to help with a camshaft? Not to my recollection. Let me know how we can help.

Hugh
 
Hi, I did email you Hugh but you only part replied to my enquiry and when I emailed again I didn't hear back. I know you're busy, no probs.
 
Hi, I did email you Hugh but you only part replied to my enquiry and when I emailed again I didn't hear back. I know you're busy, no probs.

Hrmmm.. That bums me out. I've been sick for the last few months, but I don't think I would have purposely turned you away. I apologize if so.

Hugh
 
No worries Hugh, I know how it is when you're busy and getting tonnes of email. My enquiries never seem to be straightforward! You may recall, I sent you photos of my original cam because I was worried it was too scored, you confirmed and said it'd need a regrind. So I enquired about buying a stock one you might have in already and also sent some details of some I'd seen your side of the pond which I could send to you rather than getting a regrind done here then having to ship it to the states etc etc. No probs though. I didnt wanna hassle
 
I remember now. I don't have any good core cams here right now. But if you do find a good one, or get one from Gary at Hoosracing.com - we can rephase it as needed and work it out for you. Just let me know. My apologies for any miscommunications. I've got a toddler in daycare, and she brings me every possible form of sickness lately, so I've been a bit doped up - hahaa

Hugh
 
Haha. I have a little one too so know the score. No worries. At the moment I'm talking to Jerry at Heiden who thinks he may have time to do one for me in about a months time but if that doesnt work out I'll come back to you, thanks for the offer. I've now just gotta work out the answers to my dilema to make sure I order the right thing! Everyone seems busy which is good.
 
Back
Top