Heathkit Hilltopper find and build
- Thread starter Rapidrob
- Start date
I finished the bikes wiring harness today. Not much to wire in real life. A head light On/OFF, High/Low beam, Two wires for the remote kill switch to engine ground, a head light negative back to the battery pack/charger that I still need to build, two wires from the alternator and two wires to the tail light. All the wires were run through Plastic Split Loom conduit for protection from the weather and abrasion.
Still waiting on the regulator/charger PCB to show up. Little jobs that really eat up a day.
Still waiting on the regulator/charger PCB to show up. Little jobs that really eat up a day.
Hey Rob I like this stuff far better than the old plastic split loom stuff. A piece of heat shrink on the end will lock the cover in place and protect the terminal at the same time. Very abrasion resistant and easy to use after a couple of times to figure it out.
http://rover.ebay.com/rover/1/711-5...0001&campid=5335845805&icep_item=402232273271
http://rover.ebay.com/rover/1/711-5...0001&campid=5335845805&icep_item=402232273271
Today was another long day doing little things that just take up time.
I fabricated a brace for the new muffler as it was only supported at the engine flange. I bent a 3/4x1/8x3 1/3" long piece of flat stock and drill a #10 hole on one end and a 5/16" hole in the other. A made a band strap and crimped in a pyramid double thickness stop and a flat flange to hold a 10/24 square nut. By doing this the band can be drawn very tight against the muffler body. Painted with high temp paint.
The new bearing came in for the from axle. I put those in and noticed that the spacing for the front telescoping end would rub on the new rubber boots. I fabricated a 1/4" 5/8" ID bushing to prevent this.
And I installed the new rubber boots for the open ends of the telescoping tubing of the front end.
I remounted the front end to the bikes frame having replaced the bronze upper/lower bushings for the steering column.
Still waiting on a drive sprocket and electronics which are now 10 days overdue.
new wheel bearings;
DIY muffler support bracket and band:
New fork boots;
I fabricated a brace for the new muffler as it was only supported at the engine flange. I bent a 3/4x1/8x3 1/3" long piece of flat stock and drill a #10 hole on one end and a 5/16" hole in the other. A made a band strap and crimped in a pyramid double thickness stop and a flat flange to hold a 10/24 square nut. By doing this the band can be drawn very tight against the muffler body. Painted with high temp paint.
The new bearing came in for the from axle. I put those in and noticed that the spacing for the front telescoping end would rub on the new rubber boots. I fabricated a 1/4" 5/8" ID bushing to prevent this.
And I installed the new rubber boots for the open ends of the telescoping tubing of the front end.
I remounted the front end to the bikes frame having replaced the bronze upper/lower bushings for the steering column.
Still waiting on a drive sprocket and electronics which are now 10 days overdue.
new wheel bearings;
DIY muffler support bracket and band:
New fork boots;
The 20 tooth main Jack-Shaft gear showed up this morning. I cut a chain and installed in drive system and took the bike for a test ride.
The total "gear ration" is very close to 10:1. The engine sproclet is ten tooth.Jack Shaft is now 20 tooth, JS out put is 11 tooth and the rear tire sprocket is 60 tooth.
so you have 10x20x11x60 and online calculator says it is just above 10:1.
I was going to go with a 18 tooth as a primary JS sprocket and I'm glad I did not. The engine will not climb my driveway hill ; not stalling,just will not pick up any speed.
I suppose I could put on a 28 tooth JS sprocket ,but that would really drop the speed down on the flats.
Right now the bike with me on it, the two of us in total weight of 375 pounds, the 5HP engine is just not powerful enough.
The engine is running well. The new exhaust sounds good and should not bother anyone as I ride.
I shot a short video of ride on my back road and the climb up my driveway with a running start. It will take hours to upload. I'll post it later on.
Here is a photo of the bike ready for it's first "real" ride:
The total "gear ration" is very close to 10:1. The engine sproclet is ten tooth.Jack Shaft is now 20 tooth, JS out put is 11 tooth and the rear tire sprocket is 60 tooth.
so you have 10x20x11x60 and online calculator says it is just above 10:1.
I was going to go with a 18 tooth as a primary JS sprocket and I'm glad I did not. The engine will not climb my driveway hill ; not stalling,just will not pick up any speed.
I suppose I could put on a 28 tooth JS sprocket ,but that would really drop the speed down on the flats.
Right now the bike with me on it, the two of us in total weight of 375 pounds, the 5HP engine is just not powerful enough.
The engine is running well. The new exhaust sounds good and should not bother anyone as I ride.
I shot a short video of ride on my back road and the climb up my driveway with a running start. It will take hours to upload. I'll post it later on.
Here is a photo of the bike ready for it's first "real" ride:
it seem to have good pulling power on the flats and really not that bad going up that hill/driveway for a small block mounted on a heavy bike and you on it. if your having idling problems that could have also a small affect on your power at very low end speeds. I wonder if with a little more tuning/carb and a Tecumseh hot coil on it would fix your power issue. remember too that bike was really made for a big block H motor. not saying the small block won't work. you where also saying the rod and crank making little noise? sometimes that noise can be confused with the torque converter(driver/front unit) nocking back and forth off the end of the crank because the unit is used(has excess play in it.) or not bolted down correct.
looks like you live in super bronc county......
looks like you live in super bronc county......
Yes, you nailed it! It is the torque converter that is the issue as the noise is caused just as the conning rod passes the full bottom stroke and starts to rise again at the 6:40 position.
The gap in the connecting rod cap is normal and still new ( see photos) with what I would call a little excessive side play. I was told this is normal for this engine. None of the parts on the crank or the connecting rod show any wear at all.
The carb is an issue. I bought a CHI-COM replacement and it leaked fuel so badly after ten minutes of running that I was refunded the money. The rubber seals turned to mush. I'm running the snowblower carb now.
There is a new carb coming sometimes in the distant future according to the seller.
The bike does move out well on the flats.
I need a big block 7-8 HP engine. They are not common out here at all. I have to go with what I can scrounge up.
I'm running alcohol free gas with an petroleum based octane booster.
The gap in the connecting rod cap is normal and still new ( see photos) with what I would call a little excessive side play. I was told this is normal for this engine. None of the parts on the crank or the connecting rod show any wear at all.
The carb is an issue. I bought a CHI-COM replacement and it leaked fuel so badly after ten minutes of running that I was refunded the money. The rubber seals turned to mush. I'm running the snowblower carb now.
There is a new carb coming sometimes in the distant future according to the seller.
The bike does move out well on the flats.
I need a big block 7-8 HP engine. They are not common out here at all. I have to go with what I can scrounge up.
I'm running alcohol free gas with an petroleum based octane booster.
if you have the steel cam in that engine with the factory compression release. then your half way there already just need some dyno retainers/keepers,16 pound animal springs,hot coil,billet rod,22mm mikuni carb and now the engine will pull strong up to 4700+ rpm's
see it's only money...lol $150+ worth...lol personally I like running these parts on hop up engines like this. better performance and reliability too.
see it's only money...lol $150+ worth...lol personally I like running these parts on hop up engines like this. better performance and reliability too.
have you tried to clear out the idle circuit by completely taking it out and spraying some carb cleaner though it. then some light compressed air though it.
one thing I have always notes on a small block Tecumseh is when you have that stock carb tune right and idling and all. it seems to have very good response from lowend to mid-range and ok/good top end on a stock cam with all the hop up mod's done to it. with a mikuni carb it seems to be just good lowend and mid-range to top end very good. I believe the reason behind that would be the bore sizes on the carb's are different. stock carb's bores are small and going to give you the quick response when tune correct.
one thing I have always notes on a small block Tecumseh is when you have that stock carb tune right and idling and all. it seems to have very good response from lowend to mid-range and ok/good top end on a stock cam with all the hop up mod's done to it. with a mikuni carb it seems to be just good lowend and mid-range to top end very good. I believe the reason behind that would be the bore sizes on the carb's are different. stock carb's bores are small and going to give you the quick response when tune correct.
I pulled the engine off of the bike. The seal is leaking while under "splash" pressure. I'll fix it up for a smaller bike.
I dug out my new Greyhound *196cc engine and cobbled it onto the bike. I had to raise the engine 1 1/8" to clear the jack shaft and the engines carb bowel from striking the jack shaft support bracket.
All of the wiring screwed right on with only the engine kill lug having to be replaced.
The throttle went right into the factory engine lay out with only two screws needed to anchor it into place.
What a differance! The internet says the engine is *6.5 HP. I believe it. This engine has so much torque being 10:1 through the drive that it bent the 1/8" thick steel chain adjuster on the driven wheel! Spinning that huge rear tire on the dirt road from a dead stop and nailing the throttle is all it takes.
I will have to redo the rear axle with an internal steel tube in the AM and brace the bikes rear end to take the torque.
A ride of a few miles over my dirt road and one on the mountain shows that this bike will really climb! It will accelerate UP my steep driveway hill.
Top speed is still only about 25 MPH and that is what the Heathkit brochure says it will do.
My Primary drive sprocket is 20 tooth going to an 11 tooth as as out put to the 60 tooth rear wheel sprocket. I could drop the primary down to 15 or even 12 tooth but I need to take it up my mountain first to see if the bike will really climb a steeper grade. I do not want to bog the engine down.
The muffler has to go. It is close to and is so hot on my left calf that you can only ride it for a few minutes before your pant leg is so hot you have to stop and pull it away from your skin. No shorts for sure!
The chain drive is working well so far. I probably will put a TAV onto it in the future.
I know pulling the old Tecumseh engine off the bike was a shame, but the engine really does not have enough oomph to pull me and the 175 pound bike around well.
I have an 3 Amp alternator for this engine in a box in the garage.
I need to play with tire pressure now. How the bike rides over the rough dirt roads with the "Ape Hanger" handle bars is interesting to say the least.You must stay alert for any tire tracks that are deeper than a few inches.
I don't know at this time if the tire pressure should be lower,or higher. I have no data on the recommended tire pressure from Heathkit.
I'll do a short video once I get the small bugs worked out.
* corrected CC and HP ratings
Here's a couple of photos. She is dusty for sure, but she earned it....
I dug out my new Greyhound *196cc engine and cobbled it onto the bike. I had to raise the engine 1 1/8" to clear the jack shaft and the engines carb bowel from striking the jack shaft support bracket.
All of the wiring screwed right on with only the engine kill lug having to be replaced.
The throttle went right into the factory engine lay out with only two screws needed to anchor it into place.
What a differance! The internet says the engine is *6.5 HP. I believe it. This engine has so much torque being 10:1 through the drive that it bent the 1/8" thick steel chain adjuster on the driven wheel! Spinning that huge rear tire on the dirt road from a dead stop and nailing the throttle is all it takes.
I will have to redo the rear axle with an internal steel tube in the AM and brace the bikes rear end to take the torque.
A ride of a few miles over my dirt road and one on the mountain shows that this bike will really climb! It will accelerate UP my steep driveway hill.
Top speed is still only about 25 MPH and that is what the Heathkit brochure says it will do.
My Primary drive sprocket is 20 tooth going to an 11 tooth as as out put to the 60 tooth rear wheel sprocket. I could drop the primary down to 15 or even 12 tooth but I need to take it up my mountain first to see if the bike will really climb a steeper grade. I do not want to bog the engine down.
The muffler has to go. It is close to and is so hot on my left calf that you can only ride it for a few minutes before your pant leg is so hot you have to stop and pull it away from your skin. No shorts for sure!
The chain drive is working well so far. I probably will put a TAV onto it in the future.
I know pulling the old Tecumseh engine off the bike was a shame, but the engine really does not have enough oomph to pull me and the 175 pound bike around well.
I have an 3 Amp alternator for this engine in a box in the garage.
I need to play with tire pressure now. How the bike rides over the rough dirt roads with the "Ape Hanger" handle bars is interesting to say the least.You must stay alert for any tire tracks that are deeper than a few inches.
I don't know at this time if the tire pressure should be lower,or higher. I have no data on the recommended tire pressure from Heathkit.
I'll do a short video once I get the small bugs worked out.
* corrected CC and HP ratings
Here's a couple of photos. She is dusty for sure, but she earned it....
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