PX221 - MHR very tuned - 38mm Dellorto
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Jet Eye Master
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 2439
Location: London UK
Wed Sep 09, 2020 2:00 pm quote
Honda in one piece and test ridden. Noisy and dangerous again. Awesome.

221 engine out and split.
Here is the crank wobble. Splitting the engine and taking out the crank I can do one handed in the dark. Turning the engine and holding phone steading is way more difficult. Can just make out the wobble. Its bad but casings still live on. Just need a straight crank. hmmmm.

Ossessionato
76 Sprint V, 63 GL, 62 VBB, 05 Stella
Joined: 16 Jun 2011
Posts: 2833
Location: Nashville
Wed Sep 09, 2020 2:07 pm quote
https://www.youtube.com/watch?v=Xul7WtCfi8g for those of us on Chrome.

I picked up a cheap phone tripod a while back for exactly this reason. It set me back maybe $10 on Amazon and makes things soooo much easier when you're trying to capture a video.

I'm impressed with any motor that trashes a well-made crank. I'll look forward to seeing you get it back in action.
Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and new to 2018, '66 Blue Badge Smallframe
Joined: 30 Nov 2011
Posts: 7946
Location: Victoria, Australia
Wed Sep 09, 2020 2:40 pm quote
How do you bend the end of a crank like that? Out of balance flywheel? Or is that just what we're seeing on the outside, and more hijinks are going on inside?
Jet Eye Master
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 2439
Location: London UK
Wed Sep 09, 2020 3:01 pm quote
It's quite powerful now. Well North of 40 bhp for sure. Same set up as Marco's 49 bhp one but with a bigger carb. Does 90mph sitting up, so about right. Going to down tune slightly, something I don't do often.

Big end is ok, not virgin tight anymore but a few rides left in it yet. Jap nine ball ok too. Clutch Oil seal worn flat. 11000rpm is maybe too much for a blue one, is all I had on the shelf when I last split it. Flywheel bearing is damaged.
Webs are twisted, I think it will straighten but might need a new pin.
Jet Eye Master
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 2439
Location: London UK
Sun Sep 13, 2020 12:03 pm quote
Waiting for parts. A few jobs to do while I'm waiting. Done a few today.
Changed the piston ring. Gap was 0.75mm, new one off the shelf was 0.23mm. Not terribly worn but when there's only one it matters.

Grabby clutch. The notched plate was really bent. It's supposed to be bent but not that much. I think that was not helping. I had a spare notched plate and it was much straighter. Old one in the trash. Even spinning it by hand it was smoother, think it will be fine now. Clutch all good, sip CR80 plates and heavy springs. Ready for reassembly at some point.
Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and new to 2018, '66 Blue Badge Smallframe
Joined: 30 Nov 2011
Posts: 7946
Location: Victoria, Australia
Sun Sep 13, 2020 6:50 pm quote
Jack221 wrote:
Webs are twisted, I think it will straighten but might need a new pin.
Going to weld the pin? What crank is in it again?
Molto Verboso
62 VBB1T Round Tail W/ leaner sidecar
Joined: 26 Jan 2019
Posts: 1772
Location: california
Sun Sep 13, 2020 9:47 pm quote
Just catching up.
Crank vid a bit painful...
You gotta be getting quick at stripping it down and building back up.
What do you think caused it?
Jet Eye Master
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 2439
Location: London UK
Mon Sep 14, 2020 12:50 am quote
Crank is a very pretty Pinasco one. Is a rotary crank, fully polished, flowed, bladed con rod and still in reasonable condition, apart from being bent. I have it in a local workshop now. I almost hope they can't fix it. Then I'll get a bell crank. Called the workshop and the comment was it's bad but they still thought it could be straightened.

I think just heat and power bent it. Revs violently like a dirt bike.Will be fully welded next time. With some down tune the rotary crank won't matter. Thinking I'll leave it at 40bhp and running on the hornet245 for now.
Molto Verboso
One or two fun scoots....nothing too precious
Joined: 17 Jul 2013
Posts: 1530
Location: UK (South East)
Mon Sep 14, 2020 12:56 am quote
Jack, have you strengthened your cases in any way, particularly around the input shaft?
Jet Eye Master
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 2439
Location: London UK
Mon Sep 14, 2020 12:53 pm quote
Main bearing has some work but input shaft is au naturel. Been ok for a long time but really needs the internal plate welded in. If the casings break I can get some VRone casings, there's no downside.
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