Cheap B@stard Dyno Build- HF79
- Thread starter atombikes
- Start date
A little more progress on my vertical engine mount. Had to order a 1-1/2" billet clamp (for the downtube), and a piece of .25 x 4" x 8" piece of 6061-T6 aluminum plate for the engine mount.
Will use .25" x 3" wide aluminum for the jackshaft mount, which is next.
Chain adjustability will be done by moving the jackshaft mounts.
Will use .25" x 3" wide aluminum for the jackshaft mount, which is next.
Chain adjustability will be done by moving the jackshaft mounts.
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chainmaker
Well-Known Member
Bike is looking good.
Transferred the plywood templates over to the aluminum, cut and drilled. Used a compound miter saw to cut the aluminum, even with the general purpose blade I didn't have any issues. Just make sure you wear full body protection!
Drilled all the holes on the drill press, filed all edges and corners, and here we are:
Still have to figure out the downtube mount. I'm thinking some sort of angle bracket, but it sure would be nice if I could use just a strap.
I can't see any chainline issues.
Chainmaker, your donation of those 3 billet clamps is what made me make the decision to go vertical with the engine, and kicked me into high gear to finalize the mounting. So I thank you.
Drilled all the holes on the drill press, filed all edges and corners, and here we are:
Still have to figure out the downtube mount. I'm thinking some sort of angle bracket, but it sure would be nice if I could use just a strap.
I can't see any chainline issues.
Chainmaker, your donation of those 3 billet clamps is what made me make the decision to go vertical with the engine, and kicked me into high gear to finalize the mounting. So I thank you.
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dracothered
New Member
I think you need something to tie the two plates together so the torque can't twist them and screw up your alignment.Nothing really done today; just a bunch of standing and looking at it. I did temporarily fit the rear fender to check jackshaft clearance. Looks perfect.
dracothered- you may have a point. The distance between the two plates is just under 2". I could use a threaded standoff between the two plates. One interesting point- the engine mount threaded holes on the bottom of the HF79 are EXACTLY the same distance between them as the slotted holes in the pillow blocks I am using. I thought it might be cool to just use one plate, but then realized the jackshaft would interfere with the seat tube unless they were spaced off the plate.
If any of that makes sense?
If any of that makes sense?
I got a PZ19 carb and cone filter off ebay- labrat and a couple others are apparently using these carbs to great affect, and since I have to make an intake manifold anyway (due to the vertical engine config) I thought why not?
Total price incl. free shipping for the carb and the filter was $26.
Total price incl. free shipping for the carb and the filter was $26.
thanks Big Bill for posting the dimensions on the flange. Hopefully others will also be able to use this info.
I am using an idea for the intake flanges that I got elsewhere on the forum: use cut washers as the starting point for the flanges. Turns out 3/4" washers have approx. the right ID and the OD of 2" is just about right. Soooo, one trip to home depot and $0.85 later, I've got my raw material for both flanges. I'm going to either use handlebar material (7/8" OD) or 3/4" EMT (slightly larger) for the tubing.
The carb should be positioned like this:
I am using an idea for the intake flanges that I got elsewhere on the forum: use cut washers as the starting point for the flanges. Turns out 3/4" washers have approx. the right ID and the OD of 2" is just about right. Soooo, one trip to home depot and $0.85 later, I've got my raw material for both flanges. I'm going to either use handlebar material (7/8" OD) or 3/4" EMT (slightly larger) for the tubing.
The carb should be positioned like this:
Decided this morning to finally do the engine work required to run this HF 79cc properly (remove governor and low oil sensor). Following AGK's spot-on directions, I have torn everything down and removed the two items. The only thing I did differently than AGK's directions was the removal of the flywheel nut- they recommend using an impact wrench. I used a screwdriver to hold the flywheel in place by putting the screwdriver thru one of the open unused slots on the top of the engine, and then into a hole on the backside of the flywheel. Then used a breaker bar on my socket.
even removed the camshaft to get at the oil sensor. Hope it's not a pain to get back in correctly....
The offending parts:
Next is to plug up the holes in the case and tap the new oil filler.
even removed the camshaft to get at the oil sensor. Hope it's not a pain to get back in correctly....
The offending parts:
Next is to plug up the holes in the case and tap the new oil filler.
culvercityclassic
Well-Known Member
Looks good so far. You are going to have to take the valve cover off and take the load off the springs to get the cam back in right.
I used handle bar material for my intake. The material is beter then emt.
Keep up the good work....
I used handle bar material for my intake. The material is beter then emt.
Keep up the good work....
Thanks, CCC.
I let the engine sit for a couple hrs and when I went back to it, the cam followers and lifters (I think that's what they're called) had fallen down into the engine. So, looks like I will definitely have to take the valve cover off.
Is there a specific procedure I should follow to ensure I don't screw things up when I remove the valve cover and try to get things back together?