Tim's XS project - 750cc rephased ported head titanium valve hot cam craziness
- Thread starter Tim
- Start date
Re: Tim's XS project - ENGINE UPGRADES COMING 
- AUG 2012 SALT FLATS OR BUST
Forgot I need spacers to temporarily torque down the head to get the endless cam chain over the cam sprocket. Just gotta cut 8 sections of tube about 40mm long each to span the gap. Then the cam can go in and we'll see what happens.
The left side of the crank/cam is stock, so the left piston is at TDC near as I can tell and I'm putting the cam in the stock TDC position as well. In theory it should be sorted, as the sprocket is in the original position. However it is recommended to press the sprocket off if needed and degree it in accurately. That's going to be a bit of an adventure as I don't have a press or the brains to do it.
- AUG 2012 SALT FLATS OR BUSTForgot I need spacers to temporarily torque down the head to get the endless cam chain over the cam sprocket. Just gotta cut 8 sections of tube about 40mm long each to span the gap. Then the cam can go in and we'll see what happens.
The left side of the crank/cam is stock, so the left piston is at TDC near as I can tell and I'm putting the cam in the stock TDC position as well. In theory it should be sorted, as the sprocket is in the original position. However it is recommended to press the sprocket off if needed and degree it in accurately. That's going to be a bit of an adventure as I don't have a press or the brains to do it.
Re: Tim's XS project - ENGINE UPGRADES COMING - AUG 2012 SALT FLATS OR BUST
Yeah yeah yeah. Listen, I'm clearly not running for any records.
I haven't sorted out what class I'd be in, so maybe someone can help me figure out who my competition would be.
1972 XS650 frame
1984 XS650 engine
750cc aftermarket pistons / cylinders
Rephased 277 degree crank
Shell #1 grind rephased camshaft
Ported head
Enlarged titanium intake, exhaust valves and springs from a NASCAR engine
Pamco electronic ignition
Aftermarket taller 5th gear
So, am I running against every other gas burning OHC 750cc bike on the salt? If so, I don't think I'm going to be setting many records. Too new for 'vintage', not push-rod (maybe my BMW should be going) etc.
- AUG 2012 SALT FLATS OR BUSTYeah yeah yeah. Listen, I'm clearly not running for any records.
I haven't sorted out what class I'd be in, so maybe someone can help me figure out who my competition would be.
1972 XS650 frame
1984 XS650 engine
750cc aftermarket pistons / cylinders
Rephased 277 degree crank
Shell #1 grind rephased camshaft
Ported head
Enlarged titanium intake, exhaust valves and springs from a NASCAR engine
Pamco electronic ignition
Aftermarket taller 5th gear
So, am I running against every other gas burning OHC 750cc bike on the salt? If so, I don't think I'm going to be setting many records. Too new for 'vintage', not push-rod (maybe my BMW should be going) etc.
Re: Tim's XS project - ENGINE UPGRADES COMING - AUG 2012 SALT FLATS OR BUST
Oh, BTW - cam is on, valves adjusted, and things look like they're happening when they should by eyeballing with a flashlight into the sparkplug holes. Will definitely look to put a dial in there to confirm TDC etc. but so far I think it would run like this and nothing is hitting anything. Only thing missing is some Threebond on the rocker cover.
- AUG 2012 SALT FLATS OR BUSTOh, BTW - cam is on, valves adjusted, and things look like they're happening when they should by eyeballing with a flashlight into the sparkplug holes. Will definitely look to put a dial in there to confirm TDC etc. but so far I think it would run like this and nothing is hitting anything. Only thing missing is some Threebond on the rocker cover.
Re: Tim's XS project - ENGINE UPGRADES COMING - AUG 2012 SALT FLATS OR BUST
Seriously though, I am really curious to know what class SCTA would throw me into. I can't sort where I'd be. I wouldn't mind running in the proper class, even if I have no chance at any sort of record.
- AUG 2012 SALT FLATS OR BUSTSeriously though, I am really curious to know what class SCTA would throw me into. I can't sort where I'd be. I wouldn't mind running in the proper class, even if I have no chance at any sort of record.
Re: Tim's XS project - ENGINE UPGRADES COMING - AUG 2012 SALT FLATS OR BUST
So here's how I torqued down the engine so I could get the cam chain on. With a little back and forth it went on pretty easily. Nice to not have a master link on it.
And a couple pics of the two intake valves - one closed, one open
- AUG 2012 SALT FLATS OR BUSTSo here's how I torqued down the engine so I could get the cam chain on. With a little back and forth it went on pretty easily. Nice to not have a master link on it.
And a couple pics of the two intake valves - one closed, one open
Re: Tim's XS project - ENGINE UPGRADES COMING - AUG 2012 SALT FLATS OR BUST
Sadly hit a snag. I had forgotten about one stupid little piece of tin that goes in the bottom of the cylinder head. It deflects excess oil from spraying off the cam chain into the breather apparatus.
Confirmed it was missing, which meant I had to pull the head back off. Which means the gasket is toast. I had used some Threebond in some critical areas as extra insurance against oil leaks. So new head gasket is on the way. Only $24 but, it looks like I'm loosing the long weekend to this. I think my crack dealer must be out of town as my order yesterday didn't ship like it normally does the same day. I would have gotten the gasket this morning but no delivery and no shipping email.
So will busy myself with other bits on the sides of the engine, but don't want to bolt on the clutch etc. until it's in the bike - just easier and less bulk/weight to move. Ah well. All this will make the next engine much easier. I'm going to tear down the engine that is currently in the bike to clean it all off properly and get it ready for the rigid. No rebuilding or new bits - just take it apart, soda blast the thing and put it back together with new seals and gaskets and a different head as the one on the bike now has stripped tappet studs causing a nuisance oil leak.
- AUG 2012 SALT FLATS OR BUSTSadly hit a snag. I had forgotten about one stupid little piece of tin that goes in the bottom of the cylinder head. It deflects excess oil from spraying off the cam chain into the breather apparatus.
Confirmed it was missing, which meant I had to pull the head back off. Which means the gasket is toast. I had used some Threebond in some critical areas as extra insurance against oil leaks. So new head gasket is on the way. Only $24 but, it looks like I'm loosing the long weekend to this. I think my crack dealer must be out of town as my order yesterday didn't ship like it normally does the same day. I would have gotten the gasket this morning but no delivery and no shipping email.
So will busy myself with other bits on the sides of the engine, but don't want to bolt on the clutch etc. until it's in the bike - just easier and less bulk/weight to move. Ah well. All this will make the next engine much easier. I'm going to tear down the engine that is currently in the bike to clean it all off properly and get it ready for the rigid. No rebuilding or new bits - just take it apart, soda blast the thing and put it back together with new seals and gaskets and a different head as the one on the bike now has stripped tappet studs causing a nuisance oil leak.
Re: Tim's XS project - ENGINE UPGRADES COMING - AUG 2012 SALT FLATS OR BUST
Hadn't seen the DCC Yamaha section yet - thanks for reminding me! Jason asked for some pics a bit ago. Always nice to see it up in lights.
Can't wait to see it with this beefy new engine in it. The cylinders on the big bore kit are a lot bigger all over - different fin design, so it looks different from the exterior. Of course you'll hear me coming long before you see it.
- AUG 2012 SALT FLATS OR BUSTHadn't seen the DCC Yamaha section yet - thanks for reminding me! Jason asked for some pics a bit ago. Always nice to see it up in lights.
Can't wait to see it with this beefy new engine in it. The cylinders on the big bore kit are a lot bigger all over - different fin design, so it looks different from the exterior. Of course you'll hear me coming long before you see it.
Re: Tim's XS project - ENGINE UPGRADES COMING - AUG 2012 SALT FLATS OR BUST
Ok folks - got the gasket remnants scraped off with a razor blade and cleaned off with some brake cleaner. New gasket arrived yesterday and my Pamco ignition and other bits are coming today
So with any sort of luck and perseverance I might be doing an engine swap this weekend
- AUG 2012 SALT FLATS OR BUSTOk folks - got the gasket remnants scraped off with a razor blade and cleaned off with some brake cleaner. New gasket arrived yesterday and my Pamco ignition and other bits are coming today
So with any sort of luck and perseverance I might be doing an engine swap this weekend
Rattlecan
Been Around the Block
Re: Tim's XS project - ENGINE UPGRADES COMING - AUG 2012 SALT FLATS OR BUST
Hey Tim,
We do custom suits at the shop aswell. Just drop in and see my brother Dave.
Nothing super vintage looking like the Vanson, but the NEXO suits we have are EC approved for racing.
Double check the rules to make sure what they are going to be looking for in terms saftey rating.
Also check the the rules for your helmet, most tracks around here won't even let you near the track without a minimuum SNELL 2010 helmet. They may even check your gloves and boots.
If you need any help with this stuff let me know.
Cheers
D.
- AUG 2012 SALT FLATS OR BUSTHey Tim,
We do custom suits at the shop aswell. Just drop in and see my brother Dave.
Nothing super vintage looking like the Vanson, but the NEXO suits we have are EC approved for racing.
Double check the rules to make sure what they are going to be looking for in terms saftey rating.
Also check the the rules for your helmet, most tracks around here won't even let you near the track without a minimuum SNELL 2010 helmet. They may even check your gloves and boots.
If you need any help with this stuff let me know.
Cheers
D.
