New build, straight line speed attempt...

noseoil

Active Member
#21
Back from dog-sitting for my son in Colorado, another trip to Tucson & working in the shop again. The larger tire (19/7-8 Kenda) would hit the center post I put in, so I cut it out & set 2 more in place to straddle the larger diameter rubber. Was feeling good, until I set the axle in place & mocked up the sprocket. Now the sprocket is in line with the left side post & the chain will hit along the outboard edge. Will be "trimming" the tube & making room for the chain. You can see it in the picture with the white marks where the chain will hit. I'll chop out a section & weld in a "scab" to stiffen the tube. Not worried about strength, as it's .090" wall DOM. PITA but better than letting the chain chew its way through the piece...
Exh.jpg

The exhaust is tucked in place & I left it a bit long for the RPM range this motor turns, but I can always trim it to bring up the R's once it's running again. Had to thread the needle between the frame, upright & tire side wall, but it should be good to go now. The slick is wider than the Kenda Road go.

Here's the other side with the motor in place & sitting on the mounting plate. Just missed the carb with that other tube, but it's good to go. Still a lot to do, but it's getting there. Have a trailer meet in southern N.M. this weekend, so progress is going to be slow for now. Looking for any UFO activity where we're headed.

LS-Motor.jpg
 

I74

Active Member
#23
Added,,
An old drag race trick, is to lightly put some cheap paint on the pipe, & where it stops burning the paint,, is close to where you would want to cut the pipe off,, maybe a bit past,,, so you have enough pipe left to fine tune.
That should give you a good balance between bottom end torque, & top end.;)
I
 

I74

Active Member
#24
Added again,,,
Another trick, is to get the flame angle straighter at the flange & exhaust port.
Basically you grind & contour the rear of the flange & exhaust port some, & then smooth those out.
That will help in getting the exhaust flame angled back, & not straight out & then back.
 

noseoil

Active Member
#25
Chopped out the frame where the chain would be hitting from the jackshaft to the rear sprocket, another problem solved. Cut, fill & weld, so there should be enough room now for the chain to flex & move a bit at speed. The frame member I cut is just a stiffener for the rear frame, there's another on the other side & they're both in compression, so the axial loading isn't too much since the load is split in two & it's just my butt.

Fill1.jpg
Fill2.jpg Fill3.jpg
 

I74

Active Member
#27
Looking up close at your header, it appears like the gradual bend is pretty good anyway for flow & angle, & doesn't need addressed like I described in my last post.

One thing that might help though, is to take some Pression blue ''machinist's dye'', and coat some on one the mating surfaces, & nut it together without the gasket.
Then take the pipe back off, & see how the ID of the exhaust port & flange line up.
If you notice an imperfect match, you can match port them with a die grinder , & then smooth the ports out with a flap wheel / polishing bit ect.ect.
This does help on flow & hot spots,, especially if the flange - ''in any way'' - covers the exhaust port.
 
#28
Cut and fill repair looks solid. Same method I use to join two tubes in critical areas, so it's definitely going to work there. Nice work all the way around.
 

noseoil

Active Member
#30
Brakes, having to make a bracket for the mount. A bit on the heavy side, but the only way I could get access to the bolts with the axle flange in place where I needed it. One smaller plate welds to the frame, the other one attaches to the brake caliper & then they bolt together for the mount (three 8 x 1.25 M8.8). Should be strong enough & work well. PITA to get it all aligned correctly & mounted together, but it should be OK. Still need to shape them a bit differently for the mount & trim some bolts for length...
Disc-R.JPG . Disc-2.JPG
 

I74

Active Member
#33
Rear brake set up looks very stout.
Think a few lightning holes in the caliper bracket wouldn't hurt the structural integrity at all, & look pretty cool also,, & shave some weight.;)
 

noseoil

Active Member
#35
Massacre, looks very good. Should be plenty strong & weighs less than what I came up with.

As this was my first build, I didn't leave much room for the caliper with the axle mounted this way. If I do another one, I'll mount the axle with a caliper installation in mind so there's more room for a smaller plate. I'm having to figure this stuff out as I go... Appreciate everyone's input on the build, even if I see the stuff after I've completed the work!
 

I74

Active Member
#38
You are getting there ! :)
I came up with a cool heat shield idea the other day for pipes.
Char broil makes these really neat stainless grilling sheets.
The one on the left in the pic, is what jumped out at me for a heat shield.
Figure you could trim it to fit ect. & mount it to 2 hose clamps.
Basically you run a screw thru one of the slots in each clamp, & then thru figured slots on the sheet, & then secure with nuts ect.
The pair of sheets @ Lowes is under 8 bucks, & you can use the other one for the grill. ;)
I


047362844781.jpg
 

noseoil

Active Member
#39
Had a heck of a time getting the 1/4" keyway stuff sorted out for the live axle. Basically, the drive-sprocket hub is a sloppy fit, I finally put a long key in place which is locked from moving by the outboard collar & the key at the wheel hub. Tolerances aren't really very good on the parts I got. It can't move, but it's a real PITA to have to take things apart & then reset it all again. Anyone else ever have this happen? Was tempted to just drive a single key across the entire axle to fix it so everything will stay locked in place.
 
#40
Had a heck of a time getting the 1/4" keyway stuff sorted out for the live axle. Basically, the drive-sprocket hub is a sloppy fit, I finally put a long key in place which is locked from moving by the outboard collar & the key at the wheel hub. Tolerances aren't really very good on the parts I got. It can't move, but it's a real PITA to have to take things apart & then reset it all again. Anyone else ever have this happen? Was tempted to just drive a single key across the entire axle to fix it so everything will stay locked in place.
That’s what I ended up doing, using a single long key held in place by collars on both sides
 

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