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crankwalk (Forum Supporter)
crankwalk (Forum Supporter) GRM+ Memberand SuperDork
5/10/21 12:15 a.m.

This bike caught my eye a few days ago and I recalled the excellent thread by ¯\_(ツ)_/¯  on here. 70s street legal two strokes are just cool and that era is really feeling like ancient history with every year that goes by that electric vehicles replace even emissions compliant 4 stroke engines.  I better get one before they are totally illegal. 

 

It's a 71 H1 Mach III. It just pops and bangs but has good compression but it's crusty, needs cosmetics, carbs gone through.....all the old bike things. The tank and side panels are all there and are really in great shape but they've been painted (pretty well) by are satin black. It was originally the same pretty blue as  ¯\_()_/¯ 's bike and I'm leaning toward going back to that. Accel wires, pod air filters, and I believe Denco tuned exhaust pipes. Somebody gave it some love at some point and I want to give it a little more to be presentable but i'm not going for a total restoration at this point.

 

 

 

Asymmetrical pipes are so quirky and good.

It gets the space by the Bonnie and man these were for sale at the same time. Talk about two radically different ways to skin a cat. 

First mods for me were giving it a bath, removing the skull and MC club stickers and installing a battery tender cable wink

 

Off to Ebay for a seat cover and some tune up bits but I'm excited to get started on this one. 

ShawnG
ShawnG UltimaDork
5/10/21 12:18 a.m.

Those things are nutty.

Looks like a ton of fun.

Invest in really good brake linings.

03Panther
03Panther UltraDork
5/10/21 1:16 a.m.

I had some stuff from Paul Gast at one point... "Fast by Gast" ... but all that's gone these days. 
cool stuff!

¯\_(ツ)_/¯
¯\_(ツ)_/¯ PowerDork
5/10/21 5:53 a.m.

Make sure the little choke plunger things aren't hanging up, that can keep them from starting and running correctly.

Tighten the kick starter now so the splines don't strip.

Have fun!  I don't remember anything outside of the inner workings of the ignition system being particularly confusing, and the ridiculous sound it makes as it gets into the sweet spot around 6k rpm will make any and everything you have to do to get it running worth it.

crankwalk (Forum Supporter)
crankwalk (Forum Supporter) GRM+ Memberand SuperDork
5/10/21 8:51 a.m.
¯\_(ツ)_/¯ said:

Make sure the little choke plunger things aren't hanging up, that can keep them from starting and running correctly.

Tighten the kick starter now so the splines don't strip.

Have fun!  I don't remember anything outside of the inner workings of the ignition system being particularly confusing, and the ridiculous sound it makes as it gets into the sweet spot around 6k rpm will make any and everything you have to do to get it running worth it.

Yeah your thread is a pretty great resource already.

The clutch cable is super stiff and the choke lever has to be held on place or it quickly drifts back to the open position. I'm assuming you aren't supposed to hold the lever closed and it should stay there until you ease it up yourself. So all the cables may need lubrication at least and possibly some other adjustments.

Also is there a way to tell if oil injection is working once it fires up? If I waited until I noticed the oil level drop on the sight level, I'm afraid that might be too late.  I plan on running premix until I know it works then I'd like to not run pre mix eventually.

 

I need to pick up a service manual as well since some of this stuff is straightforward and some like oil injection makes me want to really understand the system. 

 

¯\_(ツ)_/¯
¯\_(ツ)_/¯ PowerDork
5/10/21 8:55 a.m.

In reply to crankwalk (Forum Supporter) :

I think I had to hold the choke on mine too, it only needs it for a few seconds to start the thing iirc.  I think they even called it the "starting lever" or something.

There is an adjustment procedure for the oil injection but I don't remember it, if you take the side cover off you should be able to manually "throttle" the oil pump since it has its' own cable.  If you crack each fitting briefly with it running it should be obvious very quickly whether or not there is oil flowing.  I always premixed at least a little bit for some extra insurance too.

The stiff clutch may mean it needs a cable, but I'd also lube the little cam/gear thing that the cable actuates when you get a chance.  I think the clutch was pretty heavy even with everything working properly.

crankwalk (Forum Supporter)
crankwalk (Forum Supporter) GRM+ Memberand SuperDork
5/10/21 10:01 a.m.
¯\_(ツ)_/¯ said:

In reply to crankwalk (Forum Supporter) :

 

The stiff clutch may mean it needs a cable, but I'd also lube the little cam/gear thing that the cable actuates when you get a chance.  I think the clutch was pretty heavy even with everything working properly.

Mine is the stiffest clutch lever I've ever used and the brake lever is the softest. What a combo!

Meanwhile the house smelled glorious this morning. Stuck floats perhaps. I'll investigate that tonight or at least drain it. laugh

 

 

mazdeuce - Seth
mazdeuce - Seth Mod Squad
5/10/21 11:03 a.m.

I'd make sure it wants to hurt you first, then attack the cosmetics. 

crankwalk (Forum Supporter)
crankwalk (Forum Supporter) GRM+ Memberand SuperDork
5/10/21 1:08 p.m.
mazdeuce - Seth said:

I'd make sure it wants to hurt you first, then attack the cosmetics. 

I'm weird and I go backwards. If it's pretty, tagged, and insured I am REALLY motivated to get it on the street. I'm just ordering all the stuff while I go through it anyway. Now that I know I have to hold the starting lever and keep holding it while I'm kicking and not just set it, Ill give it a shot tonight. I know it has spark, compression, and way too much fuel so it should do something.  I would LOVE to drain those leaky bowls by letting the bike burn it out and fog the neighborhood. 

 

Unloading the bike off the truck yesterday, my 60 year old neighbor from a few houses down spotted the bike and knew what it was.

 "I'll have to hear it when you get it running"

Oh you will whether you want to or not. 

adam525i
adam525i GRM+ Memberand Dork
5/10/21 3:32 p.m.

Did you find it in Alaska or bring it up from the lower 48/Canada?

1SlowVW
1SlowVW HalfDork
5/10/21 6:57 p.m.

Oh yes! Fantastic life choice.

crankwalk (Forum Supporter)
crankwalk (Forum Supporter) GRM+ Memberand SuperDork
5/10/21 11:03 p.m.

Tagged and insured at lunch today so I left work early.  The first thing I did this afternoon is tighten that kickstarter as advised.


 

It was a good thing too because I got to kicking for a bit. 
 

I'll spare the first 30 minutes of kicking but success wink:
 



After it finally settled in to an idle I got greedy. Tires low, brakes questionable, forks needing a rebuild..... but I needed to shift it and see. Just a little spin up and down the street but she behaved good enough.

 

Holy crap the shift pattern is neutral then 1-5 up! I thought I had a blown first gear when I couldn't find it. Checked the downloaded service manual pdf and sure enough it's all good. 

Kill the fuel on the petcock and try to run it dry to empty those bowls.


Little puddle of premix in the valley under the carbs still appearing overfill.

When it ran out of gas, there was still an inch of fuel in the lines. Floats too high? Too low? 


 

I didn't open it up but once warm it kicked over instantly and revved great. I really think the choke lever you hold with your thumb but then let out takes practice to get right on a cold motor. Always great when the previous owner is trustworthy about running condition. Though crusty I'm more confident it's a good starting point for what I want to do with it.

 

Ordered carb rebuild kits,seat, rubbers, and the factory decals. A little cosmetic stuff keeps me motivated to do more of the mechanical stuff. Can't wait to sort it out more to take it further out but just the fact I rode it already is a relief.

¯\_(ツ)_/¯
¯\_(ツ)_/¯ PowerDork
5/11/21 5:21 a.m.

YES!  Starting it will only get easier, whether via technique or tuning, the transition from releasing the starting lever to a little bit of throttle to a happy idle is definitely a trial and error experience.  The shift pattern is the worst, I never got used to it and eventually settled on just clicking all the way down to neutral then back up into first every time I approached a stop sign.  It sounds good, I bet some fresh plugs and a little adjusting/cleaning here and there will make it happy.

Could the puddle under the carbs be one of the oil lines leaking as it runs?

crankwalk (Forum Supporter)
crankwalk (Forum Supporter) GRM+ Memberand SuperDork
5/11/21 9:16 a.m.
¯\_(ツ)_/¯ said:

 

Could the puddle under the carbs be one of the oil lines leaking as it runs?

That's what I thought but it looks like all three carbs seeping around the float bowl. It makes me think maybe it could be something as dumb as no gaskets when somebody installed it. I don't know how else the premix would be getting up there first . It's definitely gas/oil mix. Also these have brass floats I think, does anybody make plastic ones if these have pinholes and are sinking? I know I did that swap with the DCOEs on the 240z.

My eBay purchases are adding up but some of this stuff is going to take a while to get here.  New seat on the way is a replica since I can't get away with just a cover. My padding and pan are too roached.

 

I'm trying to have a lot of this done in the summer so I can hopefully get the chance to ride it a bit this year after my mini refresh. I liken this to what my pilot friends call it when somebody spray paints their Lycoming and calls it rebuilt. The "aerosol overhaul". I'm going to spend money on the original candy blue paint but the rest will be clean it up and save when I can.

 

Forks Ive never done and I've never ridden a bike with one that needed it as bad as this. Clunky. This has a steering damper on it that I haven't touched at all. That maybe a winter project and just keep it in the neighborhood at 35 mph until then.

 


 

AngryCorvair (Forum Supporter)
AngryCorvair (Forum Supporter) GRM+ Memberand MegaDork
5/11/21 9:22 a.m.

berkeleying cool!

GCrites80s
GCrites80s HalfDork
5/11/21 12:14 p.m.
crankwalk (Forum Supporter) said:
¯\_(ツ)_/¯ said:

 

Could the puddle under the carbs be one of the oil lines leaking as it runs?

That's what I thought but it looks like all three carbs seeping around the float bowl. It makes me think maybe it could be something as dumb as no gaskets when somebody installed it. I don't know how else the premix would be getting up there first . It's definitely gas/oil mix. Also these have brass floats I think, does anybody make plastic ones if these have pinholes and are sinking? I know I did that swap with the DCOEs on the 240z.

My eBay purchases are adding up but some of this stuff is going to take a while to get here.  New seat on the way is a replica since I can't get away with just a cover. My padding and pan are too roached.

 

I'm trying to have a lot of this done in the summer so I can hopefully get the chance to ride it a bit this year after my mini refresh. I liken this to what my pilot friends call it when somebody spray paints their Lycoming and calls it rebuilt. The "aerosol overhaul". I'm going to spend money on the original candy blue paint but the rest will be clean it up and save when I can.

 

Forks Ive never done and I've never ridden a bike with one that needed it as bad as this. Clunky. This has a steering damper on it that I haven't touched at all. That maybe be a winter project and just keep it in the neighborhood at 35 mph until then.

 


 

That carb rebuild kit looks more like a PC game from 2000 than bike parts.

crankwalk (Forum Supporter)
crankwalk (Forum Supporter) GRM+ Memberand SuperDork
5/11/21 12:43 p.m.
GCrites80s said:

 

That carb rebuild kit looks more like a PC game from 2000 than bike parts.

 

While 36 bucks wouldn't be a value for an ancient PC game bought at Office Depot in 2000, I'd not be totally disappointed either. I buy the brand name Amal parts for the triumph since the off brand ones are terrible but I've never had bad luck doing Keihin or Mikunis with cheaper stuff.  

BrianC72gt (Forum Supporter)
BrianC72gt (Forum Supporter) GRM+ Memberand New Reader
5/11/21 4:25 p.m.

It didn't try to kill you, is the engine broken?  My daily is a Ducati MTS1200 with 150hp on tap,  and I wail on it, but these things still scare me.  I might have been 16 when I rode the H2,  it was mind altering.  A visceral little misbehaving beastie.  Looks like fun.

 

GCrites80s
GCrites80s HalfDork
5/11/21 8:10 p.m.

I think my buddy's dad crashed his H2s 5 times in the '70s and early '80s.

03Panther
03Panther UltraDork
5/11/21 8:37 p.m.
BrianC72gt (Forum Supporter) said:

It didn't try to kill you, is the engine broken?  My daily is a Ducati MTS1200 with 150hp on tap,  and I wail on it, but these things still scare me.  I might have been 16 when I rode the H2,  it was mind altering.  A visceral little misbehaving beastie.  Looks like fun.

 

We had a "all HD" dirt drag track near me in the 70's 80's and 90's 

a friend started racing a 'zuki 500 two stroke. Didn't last long before theybuilt a H1 500 triple. It was right radical. Then they did a 750 triple. Only discription comes to mind is "oh my gawd!!!"

Red said "ya know the H1 is faster than other 500's. Figured I could judge the difference from other 500's and 750's, and this would be a bit more... a BIT more don't come close! "

Only H1 I ever rode on the street, had some of the 500's race bike arts on it, including the longer swing arm  (before that was a poser thing) and, although a riot to ride, was not scary or unpredictable. 
The 750 triple, on the other had earned its "Widow Maker" moniker. 

 

Sidewayze
Sidewayze Reader
5/11/21 10:32 p.m.

Just a quick thought.  Be careful running premix in a 2 stroke that's not jetted for it.  Adding oil to the fuel leans out the mixture.

crankwalk (Forum Supporter)
crankwalk (Forum Supporter) GRM+ Memberand SuperDork
5/15/21 10:51 p.m.

No leaks but I really hate rust.
 

I pulled the tank and oh my. Thats an interesting solution.

Full of rust:

 

I found the top screen in the tank and cleaned/disassembled the petcock. Looks better to me.


Rust remover soak
Tank liner time:


 

 

I love that stuff. I've had such good luck with it sealing the rest of the rust and never leaking.

 

Replacement decals arrive a little curved but should be usable. Dropped the metal work off at paint.

 

Now that the bike is a little more naked I'll have some more room to work. A little touch up paint, polishing the brightwork, and cleaning up wire routing:

Before:


 

And after. Built not bought y'all. cheeky

 

 

 


Carbs off and I inspected the oil lines. They look good and I think all my leaks were from the bowl gaskets.

Carb kits that look like Road Rash on Sega Game Gear appear to have the right stuff per the manual.

^Pretty large barb with a massive vacuum leak.

 

The new kit had varying differences on the size of washers and brass but it all evened out.


 

My favorite carb cleaning tool is made by D'Addario. This is going on a Guild dreadnaught later tonight:


 

 

Assembled and back in. Cables feeling great now.

 

 

I'm missing the little dampener knob but jeez those are expensive. I'll break down and buy one after paint I'm sure.

 

^This regulator box looks newish.  I didn't see any markings on it to get a brand though.


 

That catches us up to the first 6 days of ownership. Waiting on the new seat to arrive and parts to be painted. Until then her new spot is in the furthest corner for a few weeks:

crankwalk (Forum Supporter)
crankwalk (Forum Supporter) GRM+ Memberand SuperDork
5/22/21 2:32 p.m.

My current right side head has some broken fins and that bugs me. 

 

So I picked up a replacement for $17 shipped. It was in great shape except it was filthy. This is after brake cleaner and degreaser:

 

A local machine shop bead blasted it for me in five minutes for free. They were paid in surprise pizzas at lunch.

 

 

The old head gasket was definitely leaking  anyway.

 

 

Heat up the new gasket using a camp stove the drop it in some water. You would think this doesn't get hot enough but it will glow and I've never had an issue.



 

Torqued this and the other heads down to 16 ft lbs.


 

Apply ancient Denco decal from the 70s:

 

Seat has shipped and still just waiting on the call from paint.

crankwalk (Forum Supporter)
crankwalk (Forum Supporter) GRM+ Memberand SuperDork
5/29/21 8:48 p.m.

Day 19.

 

NOS NGK surface gap BUHX plugs:


 

The new seat came in and its excellent fitment and quality. That's a pleasant surprise.

 

Back to the original candy blue by Perry's Rod and Custom in Wasilla.

 

 

Still needs a fork rebuild and I want a new front fender eventually since this one is trimmed back. That's stuff I can do over the winter but at least it's presentable and good enough to putt around here. No more flat black and skulls! 

ShawnG
ShawnG UltimaDork
5/29/21 10:54 p.m.

Damn, that was fast!

Looks great.

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