Joe's two stroke collection

[Goat]

Starting a thread for my blue smoke projects. God i love two strokes.

Currently ripping into my 1973 H1 500.
I bought this bike years ago (2015 i think). Went to look at it with @kicker and a deal was made. It was a US import that had been sitting in NZ for a few years. I got it complied and legal by the end of that year. Didn't even have my licence then! Never rode it. hah.

Got the tins painted by @Bellicose on here. He did an amazing job. Has sat in my bedroom on display ever since. Started it up a few times at partys for lols. But never took it on the road.

I did get a wof on it once. And rode it to an oldschool meet. But what a turd. It surged and bogged all over the place. I could also never get it to idle. It was actually pretty sketchy to ride with its surging and bogging. So parked it back up again on display.

Until now....

[GregT]

They're sensitive to carb synch. Not sure if it's on that year but early ones have a plug in the side of the carbs to let you see the slides.  But better to vacuum synch anyway. The late ones like yours lost quite a lot of power compared to the earlier models Plug sensitive too. Has it still got surface gap plugs ?

i owned and raced a blue model. CDI ignition but still a drum front brake. The White first years, the red next up and the blue ones all had the same barrel porting so all were full power. I used to have an article with the full noise port timings but it's long gone. White and red ones had points ignition.

[Goat]

Yeah, the H1s got progressivly "tamer" the longer the model ran, all sorts of regulation kept restricting them. The last of the line 1976 KH500 a8 is actually lams approved lol. A long way from the "widowmaker" reputation of the early drum front models!
I've got a drum front one awaiting restoration. Currently accumulating bits for that. Anyway, back to this saga.

First step, get it out of my room and onto the operating table. The dudes at bike night were more than happy to provide motivation support.

So last time i had this running, the carbs were pissing out fuel, so took it apart and found that the floats had been eaten by whatever gas was in it. I managed to solder two of them up, but the third i had to pinch a float from my other h1 (1971 H1a) to get this running.
I knew i needed to go through the carbs again and fit a new set of floats, and probably jets and needles too. The slides had seized from sitting. So off with the carbs and managed to get the slides out.

I proceeded to whip the carbs off and take them apart to inspect:

They were pretty clean inside, but one of the needle holders was loose as a goose. Looks like the securing brass pin had been eaten away. So will need to figure out how to re-pin this when the carbs go back together.
The jets were pretty skodey (though not blocked) and the needle holders had seen better days. So will get new everything to biff in.

I though i'd pull off the sidecovers to give them a bit of a cosmetic resto, Removing the stator cover, and about a thrid of a litre of two stroke oil came out.... this isn't good... You can kinda see the tide mark in the pics.

This isnt looking good. It means that:
a) The oil check valves are definitely tired/not working. So will get new springs and balls for those. They seem to be the rebuildable type, so thats a bonus.
b) The crank seal on this side (and probably all the crank seals) are rooted, so that is probably one of the main reasons for its shitty running.

Looks like i'll need to pull the engine out, split it, and get the crank rebuild. This will be a great oppertunity to get the engine cases blasted as they look a bit skungey. Cool, more work and $$. Thank god i love the misery.

Should be finishing the Laverda, but that;s not a passion project, I love two strokes and Ducatis, The Laverda just looked like a good buy at the time (it wasn't) and i'm too far down the rabbit hole to bail now. hah

Probably will need a new stator, and potentially ignition pickups too as god know how long they've been soaking in oil.

[Flauski]

Oooof, always wanted one of them. 

You've got all the cool toys. 

[Snoozin]

Dad just got his one (1969, red tank, unrestored, owned for 40 years or so) running again, apparently I'm allowed to ride around on it when I get my restricted (his permission, not the laws). We should have an H1 meet and make some blue smoke.

[Goat]

So yeah, found the problem why it was running so bad:

/mitsi ain't that bad.

But yeah, the crank side seal is chooched. Like zero crank compression, all comes out the side seal. Can hear it huffing out the side! I could just replace that i suppose? But the other seals are probably not far behind. So engine out it is!

I'll get the cases blasted while i have them apart. So hopefully the motor will look awesome once its done. A bit of a shame the frame looks like this:

Ah well, better strip it all the way down and get the frame blasted!

Not bad for a quick carb rebuild eh! lol. Nothing is ever easy

 

 

 

Also, here is the blue 1971 H1a drum front, back when i picked it up with @Beaver and @kicker back in 2015!

It looks like a wreck, because it is. It is about 95% complete though. So if anyone knows of any parts, lemme know! As i'll hopefully be cracking into this later this year.

 

[Goat]

I stripped the engine down to get the crankshaft out.

Oil check valves are definitely chooched:

Bloody murder!

Guts out:

 

Not only were all the crank seals as loose as chatter rings, one of the bearings had completely collapsed. You can see it next to the stator on the right side of the crank in the above pics.
I'm amazed this thing ran at all.

 

However, there is some bad news...

Because of this collapsed bearing, its actually had been spinning in the crank cases and has wallowed out the bearing surfaces....
Shits dicked jim. Theres about a 0.5mm lip there.

I know there are various ways to fix this, like peening some divots in the surface to raise it up then locktite 620 the bearing in, but that feels a bit michael mouse, and it would always bug me. Plus, seeing one can still (relatively) easily get casings, I'm on the hunt for some good cases now.

Good news though, i've got everything i need to do a bottom end rebuild on its way. So hopefully i can source some good cases soon and progress this revival!

[triumph...tristan]

I will be enjoying the progress of this thread. I have a 1970 H1. They are incredible bikes!

[GregT]

Have you asked around to find someone to rebuild the crank ?  It's fast becoming a lost art in NZ.

If you can't come up with good cases, it's not too hard to set up and machine that bearing housing oversize. Then a pegged sleeve back to OE size.

[Goat]

I'm gonna have a crack at rebuilding the crank myself. Allen Millyard has a very confidence inspiring video on rebuilding his H1 crank.

I've got 2 H1 cranks and a couple of twin and single cranks in my list to rebuild. So if I can learn how to do it, maybe I'll be the next two stroke crank guy in NZ? probably not. But at least I won't be paying someone else top dollar to fuck it up! Only have myself to blame.

Gonna use the money I'd spend on rebuilding a crank buying the required tools etc.

As for machining the cases, looks like I can get a tidy set of cases between $400 and $600 to my door. I very likely won't get any change out of $18k getting that stuff machined locally.

Every experience I've had with NZ people in the trade seem to:

• Have a "I can't be fucked" attitude like they're doing me a massive favor or something. Dude, I'm paying your for a service! No need to be like that!
• Be eye wateringly expensive
• Or they fuck it up anyway and I have to get it redone or buy a replacement

So I'm very reticent to pay someone to do it (repair cases or rebuild crank). When at least if I do it and fuck it up, I've only got myself to blame, and I haven't outlaid heaps of money for the privilege. 

[GregT]

My immediate reaction to reading that was - you're in the North Island. Talking to my customers from up north over many years, the SI pricing has invariably been lower for one-off jobs.

Best of luck doing the rebuilds. If you chicken out, I can point you at two good guys down here.

[cubastreet]

Wanna get together on the crank rebuild? Might give me the inspiration required to get back onto my T500

[Goat]

Yeah man. Will let you know when im gonna tackle it. Feel free to pop over!

T500! Rad! What year?

[cubastreet]

It's a 71. I got as far as pressing the crank apart then life got in the way. 

[Goat]

Rad! I've got a 71 aswell. Just in the process of giving mine a wee refresh. Some new carb rubbers and intake rubbers along with new cables.
Super keen to help you rebuild your crank! Currently sourcing bits of steel to help with crank pressing

[Goat]

The saga continues. Did some blasting over the long weekend. Have all the barrels, heads and carbs blasted. It took a wee while!

I've also managed to acquire some good condition cases for a good price. So they're on their way now. Yay.

Carbs before:

 

Carbs after:

 

Barrels before:

 

Barrels after:

 

 

Cylinder head after:

Leik new!

This is using glass powder, so it leaves a finish very close to vapor blasting. It doesn't mar or hold dirt like the "furry" sand blasting finish. Ideal!
 

 

[cubastreet]

I think I still have a steel plate with a slot cut in it that I used to press apart my crank if that's useful?

[Goat]

@cubastreet Should be all good thanks, Currently trying to secure various bits and pieces for an assortment of pressing bits. What's the OD of your crank webs?

Gonna get a section of steam pipe to use for crank pressing, should make sure it can fit t500 cranks too

[cubastreet]

I just measured it 120mm

[Goat]

Chur, will make sure i'll get >120ID. h1 is 110. So good we checked!