Gradientthorr
Fabricator for HHB
Thank you sir
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First Build: 1979 Trackerthingymajiggerwhatchamacallit
- Thread starter Gradientthorr
- Start date
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- Tags
- build custom fabricating pictures
Augie
Augie
If I had access to a tube bender and as much gumption as you I'd be doing exactly what you're doing. Looks radical! Can't wait to see the end product.
angus67
Welder's penetrate deeper!!
well, gradient, you changed your avatar. any changes with the bike?
augie, welcome. Start a intro thread. put what bike you are working on in your signature. That way, fredintoon wont get pissy. although entertaining, we would like to know what your working on when the time comes.
Look at my signature. The stock bikes are just year and mileage. The custom, or steered away from stock are given a brief description.
apply judicious amounts of the search function to keep 650 skull at bay.
augie, welcome. Start a intro thread. put what bike you are working on in your signature. That way, fredintoon wont get pissy. although entertaining, we would like to know what your working on when the time comes.
Look at my signature. The stock bikes are just year and mileage. The custom, or steered away from stock are given a brief description.
apply judicious amounts of the search function to keep 650 skull at bay.
scabber
XS650 Guru
Looks good nice work and fab skills. I would go with disc break rear wheel.
Gradientthorr
Fabricator for HHB
Alrighty folks,
Been forever since I've worked on this pig. Finally got around to mounting my seat pan to the frame. My timeline is in decades now instead of months haha. I threw our mock-up engine in the frame a while back. All the mounts seem to be in the right spot. I'm going to run a set of our HHB lower motor mounts and a custom set for the top. I could probably make a cool set of mounts, but I know the guy who employees the guy who makes these, so yeah. One thing I will be doing in the near future is milling my head cover. Turns out a husqvarna dirt bike tank was never meant to fit an XS. WHO KNEW?! So I'll be taking a bit of width out of the top mounts on the head cover to clear the tunnel. Also, I've got this idea for a head job. I'm taking a factory head and welding up some of the combustion chamber. My thinking is that it'll give me a bump in compression while at the same time creating better chamber geometry to prevent detonation. Hopefully making a smaller volume chamber with less surface area for the charge will help lower the likelihood of detonation. Plus, I just want to do something that I haven't seen before. The head will get alot more work on the intake and exhaust ports for sure. Tell me what y'all think, but only if it's criticism of the work. I don't care if you think my momas a hoe. That's a matter of opinion between her and the milkman.
PS. We went to BMR this year and it was flipping fun! Had a blast with alot of great friends and saw a ton of killer bikes. Rode alot if great rodes, got sun poisoning, saw hugh drunk as a skunk, and made it home in one piece. If ya haven't been ya need to go.
PPS. Going to send my seat to pj as soon as I can figure out what I want.
Been forever since I've worked on this pig. Finally got around to mounting my seat pan to the frame. My timeline is in decades now instead of months haha. I threw our mock-up engine in the frame a while back. All the mounts seem to be in the right spot. I'm going to run a set of our HHB lower motor mounts and a custom set for the top. I could probably make a cool set of mounts, but I know the guy who employees the guy who makes these, so yeah. One thing I will be doing in the near future is milling my head cover. Turns out a husqvarna dirt bike tank was never meant to fit an XS. WHO KNEW?! So I'll be taking a bit of width out of the top mounts on the head cover to clear the tunnel. Also, I've got this idea for a head job. I'm taking a factory head and welding up some of the combustion chamber. My thinking is that it'll give me a bump in compression while at the same time creating better chamber geometry to prevent detonation. Hopefully making a smaller volume chamber with less surface area for the charge will help lower the likelihood of detonation. Plus, I just want to do something that I haven't seen before. The head will get alot more work on the intake and exhaust ports for sure. Tell me what y'all think, but only if it's criticism of the work. I don't care if you think my momas a hoe. That's a matter of opinion between her and the milkman.
PS. We went to BMR this year and it was flipping fun! Had a blast with alot of great friends and saw a ton of killer bikes. Rode alot if great rodes, got sun poisoning, saw hugh drunk as a skunk, and made it home in one piece. If ya haven't been ya need to go.
PPS. Going to send my seat to pj as soon as I can figure out what I want.
Well, THAT's different. Shoving the combustion chamber volume over towards the plug?
Keep an eye on the spark advance with that one. A chamber/advance chart in here:
http://www.xs650.com/forum/showthread.php?t=45197
DrewMartin
Old fashioned new guy
Needs more quench...
Curious to see how this turns out. As I'm sure you know, it'll need different pistons to take advantage of the new chamber.
*editing to leave a less vague message*
Take a look at some of the higher performance/high dynamic compression ratio engines and almost all of them have large flat spots in the combustion chamber referred to as "quench" or "squish". If you can reduce the surface area of the combustion chamber you can significantly reduce the chance of detonation occurring due to less than desirable aspects of the combustion chamber. Even though most of these examples are 4 valve, pent roof designs, the same still holds true for 2 valve hemi/semi-hemi designs. Care must be taken with this though to ensure you aren't shrouding the valve and restricting flow. I might have to dig up some of my old SAE books regarding engine design and theory.
2one7 chops
XS650 Enthusiast
Your build makes me feel like a slacker, great job and hats off to you!
Gradientthorr
Fabricator for HHB
Great thread! That's exactly what my thinking has been for a while. More spark advance leads to more negative work on the piston. I think a long rod conversion with high compression and barely any advance at all would be the cats pajamas. As for setting the advance, well....I think I know a guy that can help with that
we've got a few things in the works for the performance enthusiast. Thanks for the info and support! I'd love to talk shop if you're down
Gradientthorr
Fabricator for HHB
I totally agree. If I had the time and motivation I would fill that chamber up completely, adjust the valve angles,raise the ports and use a flat top piston. But, I just want to try and improve on what I've got. I want to finish the project, ride the piss out of it, then move on to the next more wild one. It does need more quench, but this is the best I can get without doing major surgery. Thanks for the input! You guys on this blog know alot more than I do. I'm new to the community and don't know all the information that's on here so any help will be greatly appreciated!
Gradientthorr
Fabricator for HHB
I totally agree. If I had the time and motivation I would fill that chamber up completely, adjust the valve angles,raise the ports and use a flat top piston. But, I just want to try and improve on what I've got. I want to finish the project, ride the piss out of it, then move on to the next more wild one. It does need more quench, but this is the best I can get without doing major surgery. Thanks for the input! You guys on this blog know alot more than I do. I'm new to the community and don't know all the information that's on here so any help will be greatly appreciated!
member3480
RICH
Very different Nice workDrewMartin
Old fashioned new guy
You're already off to what I'd say is a great start, my post was merely just general information on why this theory makes sence. I 100% understand not wanting to spend too much time on a project so you can move on to the next. Truthfully if you really wanted to do that much work it would probably be easier to pack a cylinder head full of clay and have a casting house use it as a buck for a mold.
Gradientthorr
Fabricator for HHB
Now, for my next trick:
Been so long since I've posted anything. I can't remember what has and hasmt happened since. I know I reworked my front end to utilize Harley sportster triple trees, made some upper motor mounts, cut up a perfectly good tank, and started on my headlight mount/number plate. I don't have anything clever or witty to say. Life is not so much fun right now. Nursing a dying parent is no fun at all.
Anyways. Here's some pictures. More to come. Oh yeah...I ported my head too. Learning through doing. Not an expert. Just an experiment
Been so long since I've posted anything. I can't remember what has and hasmt happened since. I know I reworked my front end to utilize Harley sportster triple trees, made some upper motor mounts, cut up a perfectly good tank, and started on my headlight mount/number plate. I don't have anything clever or witty to say. Life is not so much fun right now. Nursing a dying parent is no fun at all.
Anyways. Here's some pictures. More to come. Oh yeah...I ported my head too. Learning through doing. Not an expert. Just an experiment
Looking rad! Can't wait to see the next bit! Also I'm sorry to hear of your current family predicament. I know the feeling all too well. Here's to working through it and keeping the positivity.
Gradientthorr
Fabricator for HHB
Thanks bud! Busy hands are happy hands
hutch311
XS650 Member
Sub'd. This is an inspiring build. Keep your head up. Look forward to the updates.
I've seen a couple of camcovers in here with cracked top motor mount ears. Probably from overtightening. Might consider fitting some spacers in yours...
