1972 Honda XL250 - Page 4

mjn · 07-29-2012, 02:35 PM

Lookin good man!

Phlebmaster · 07-29-2012, 07:41 PM

More progress!! Keep it up!

Andy Capp · 07-31-2012, 01:36 AM

Thanks guys. Chip, chip...

nsrg500 · 07-31-2012, 02:15 AM

I've been over to see the bike (XL) but I have to be here at home on the computer to actually see it all together.

P.S. I remember looking at the work on the petcock, thinking "man that dude has some time on his hands"

Andy Capp · 07-31-2012, 08:52 PM

Originally Posted by nsrg500

I've been over to see the bike (XL) but I have to be here at home on the computer to actually see it all together.

P.S. I remember looking at the work on the petcock, thinking "man that dude has some time on his hands"

Dont worry this bit isn't very exciting. Mainly cleaning. If you got a valve spring compressor you are more than welcome to come for midnight beers

Lol yeah I spent way too much time on the petcock but there is only so much I can do while looking after the snot gobbler. I got plenty of time not to do any meaningful work on the bike......and don't even mention the moss

Andy Capp · 08-02-2012, 12:39 AM

Got a couple of things done this evening

Andy Capp · 08-10-2012, 12:21 AM

I found a couple of hours at the end of an 18h day to find a little more than I bargained for....

Bumming......

nsrg500 · 08-10-2012, 05:39 AM

I could weld that back together for ya.

How is the valve? Bent?
I didn't notice and nicks in the piston, but wasn't looking looking for any either.
That's kind of a good thing. Easy fix and could explain a few things.
New springs are like $10?

Should grind of about a 1/4" off that head and bring the compression up. Might want to file it flat again before you put it back together though???

Andy Capp · 08-10-2012, 07:31 AM

Originally Posted by nsrg500

I could weld that back together for ya.

How is the valve? Bent?
I didn't notice and nicks in the piston, but wasn't looking looking for any either.
That's kind of a good thing. Easy fix and could explain a few things.
New springs are like $10?

Should grind of about a 1/4" off that head and bring the compression up. Might want to file it flat again before you put it back together though???

Luckily it was the second/inside spring and the reason I didnt see it before. The valve stem seems straight and the only damage seems to be the top of the guide. I know it's not the end of the world but I was not expecting it. They are also longer after-market springs so I'm not sure, at this point, how available they might be.

I know it's not the "proper" thing to do but if the clearances are good can I use one of the valve guides from the spare head I have?

nsrg500 · 08-10-2012, 07:52 AM

Originally Posted by Andy Capp

Luckily it was the second/inside spring and the reason I didnt see it before. The valve stem seems straight and the only damage seems to be the top of the guide. I know it's not the end of the world but I was not expecting it. They are also longer after-market springs so I'm not sure, at this point, how available they might be.

I know it's not the "proper" thing to do but if the clearances are good can I use one of the valve guides from the spare head I have?

Sure you can. If you can get them out without damaging them?
If you really need to go that route. I'd use the valves and guides from the other head. The guides are going to be mated to the valve, valve to seat. Have to re-lap the valves. Might be more work in the long run?
Isn't that stuff really cheap? I'd check around and see what that stuff costs first. Might only be into it for $20, two springs, seals and guides. Or just go after market and see what they have to offer?
I'm assuming you haven't priced any of it yet?

Andy Capp · 08-11-2012, 07:59 AM

The damaged guide came out easy enough. Getting the other (spare) one out undamaged might be a challenge because of shape of the guide at the manifold end and since it turns out I don't have a suitably sized drift.......oh wait......I don't even own a drift or parallel punch lol. Fuck, What am I doing.......I got no business buying a non-runner.

New might be a better option. I found an exhaust valve guide on fleebay for $15 (which might be good for the other slack one I have) and an inlet from Holland @ €15. I haven't found any source for the longer springs yet.

Oh wise ones, what is the reason behind the longer valve springs? Is it to ensure the speed of the valve closing because of the high lift cam profile? The inside spring is to prevent bounce, right?

On the plus side the seats don't look too bad.

NoMornings · 08-11-2012, 12:04 PM

Originally Posted by Andy Capp

Oh wise ones, what is the reason behind the longer valve springs? Is it to ensure the speed of the valve closing because of the high lift cam profile? The inside spring is to prevent bounce, right?

The longer springs are to prevent coil bind (where the spring is bottomed out and can't get any shorter) which the high lift cam could otherwise cause. The inside spring is to prevent bounce/valve float, at least in part by moving any resonance periods outside the range of likely attainable rpm.

nsrg500 · 08-11-2012, 12:12 PM

Originally Posted by NoMornings

The longer springs are to prevent coil bind (where the spring is bottomed out and can't get any shorter) which the high lift cam could otherwise cause. The inside spring is to prevent bounce/valve float, at least in part by moving any resonance periods outside the range of likely attainable rpm.

yep.

Andy Capp · 08-11-2012, 01:08 PM

Originally Posted by NoMornings

The longer springs are to prevent coil bind (where the spring is bottomed out and can't get any shorter) which the high lift cam could otherwise cause. The inside spring is to prevent bounce/valve float, at least in part by moving any resonance periods outside the range of likely attainable rpm.

Got ya. Thanks.


07-29-2012, 02:35 PM	#61
mjn Joined: Jul 2005 From: Tri-Cities Blog Entries: 1 I Ride: '05 Busa, '03 KLR 650, '81 Seca 550, '78 Hawk, '71 SL 350, '69 Z50A	Lookin good man! __________________ Follow PNW Riders on Facebook and Twitter


07-29-2012, 07:41 PM	#62
Phlebmaster Chicken Strips Joined: Jan 2012 From: Oregon City I Ride: 1984 Porsche 944- 1987 VFR750 Traded- 1985 VF500f Interceptor traded- 1976 KZ400 traded	More progress!! Keep it up! __________________ Follow PNW Riders on Facebook and Twitter


07-31-2012, 01:36 AM	#63
Andy Capp Superbiker Joined: Oct 2010 From: Everett, WA I Ride: 05 GSX-R750, 08 675, 72 XL250	Thanks guys. Chip, chip... __________________ Follow PNW Riders on Facebook and Twitter


07-31-2012, 02:15 AM	#64
nsrg500 Shredder Joined: May 2011 From: Everett. WA I Ride: GS1150 Rat bike, NSR(G)500cc two stroke,CBR 900rr	I've been over to see the bike (XL) but I have to be here at home on the computer to actually see it all together. P.S. I remember looking at the work on the petcock, thinking "man that dude has some time on his hands" __________________ Follow PNW Riders on Facebook and Twitter


08-02-2012, 12:39 AM	#66
Andy Capp Superbiker Joined: Oct 2010 From: Everett, WA I Ride: 05 GSX-R750, 08 675, 72 XL250	Got a couple of things done this evening __________________ Follow PNW Riders on Facebook and Twitter


08-10-2012, 12:21 AM	#67
Andy Capp Superbiker Joined: Oct 2010 From: Everett, WA I Ride: 05 GSX-R750, 08 675, 72 XL250	I found a couple of hours at the end of an 18h day to find a little more than I bargained for.... Bumming...... __________________ Follow PNW Riders on Facebook and Twitter Last edited by Andy Capp; 08-10-2012 at 12:24 AM..


08-10-2012, 05:39 AM	#68
nsrg500 Shredder Joined: May 2011 From: Everett. WA I Ride: GS1150 Rat bike, NSR(G)500cc two stroke,CBR 900rr	I could weld that back together for ya. How is the valve? Bent? I didn't notice and nicks in the piston, but wasn't looking looking for any either. That's kind of a good thing. Easy fix and could explain a few things. New springs are like $10? Should grind of about a 1/4" off that head and bring the compression up. Might want to file it flat again before you put it back together though??? __________________ Follow PNW Riders on Facebook and Twitter


08-11-2012, 07:59 AM	#71
Andy Capp Superbiker Joined: Oct 2010 From: Everett, WA I Ride: 05 GSX-R750, 08 675, 72 XL250	The damaged guide came out easy enough. Getting the other (spare) one out undamaged might be a challenge because of shape of the guide at the manifold end and since it turns out I don't have a suitably sized drift.......oh wait......I don't even own a drift or parallel punch lol. Fuck, What am I doing.......I got no business buying a non-runner. New might be a better option. I found an exhaust valve guide on fleebay for $15 (which might be good for the other slack one I have) and an inlet from Holland @ €15. I haven't found any source for the longer springs yet. Oh wise ones, what is the reason behind the longer valve springs? Is it to ensure the speed of the valve closing because of the high lift cam profile? The inside spring is to prevent bounce, right? On the plus side the seats don't look too bad. __________________ Follow PNW Riders on Facebook and Twitter

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