Re: Treats puch-hobbit head hard to impossible start?

The red was a sharpie to test whether the head is flat. So with the two copper washers the motor starts initially and ran great but wont restart until it totally cooled. The heat fouling is probably happening still because the upper part of the threads aren't into the metal of the head so the plug I believe heats irregularly.

Anyway my verdict is these heads with too much material removed exposing plug threads are basically unuseable. Don't buy them is the verdict.

Re: Treats puch-hobbit head hard to impossible start?

That may be your verdict .

It seems to me something else is amiss . But ???

Re: Treats puch-hobbit head hard to impossible start?

So there is a reason almost all spark plugs are long reach and the relatively underpowered ones use short reach and now this head is too thin even for a short reach. It probably has all to do with heat propagation away from the combustion chamber. The derbyetrakit head makes a.great Hobbit head in part because it uses a.long reach. Tomos.uses.long reach and they are near pervious to issues. Grahms latest version sold at dos cycles is solid metal.all.along the path of the plug and im sure won't don't this. It's only flaw is the absence of a squish band but at this point I think it's going to work just fine on this mild build.

I've got a.bet with myself what when I go.out into the garage in a few to.see the redmhonda that has been sitting all night equilabrating it will start right up.

Re: Treats puch-hobbit head hard to impossible start?

So as I predicted. Starts and ends rides well. Then wont restart when hot. Plug left to equilibrate over night , starts on first pull. This is heat fouling.

Re: Treats puch-hobbit head hard to impossible start?

15564047532292387019990565514087.jpg
15564047025016712435453806903141.jpg

Jailing here we come. Just needed to loosen the pipe. M7 126 Vespa studs

Re: Treats puch-hobbit head hard to impossible start?

kevin Smellaflange /

try to index your plug, you want the open end of the electrode to be open to the intake side.

Re: Treats puch-hobbit head hard to impossible start?

Perfect start. Perfect immediate restart Max temp at work 380 then on way back crept up to 406 into the wind. Im not sure if all my new and old 126 studs are up to this task. The two new ones are perfect to torque. The two reused ....I wish I had bought two sets of the Vespa 126 because for some reason one was m6-m7 I'll probably get two new ones. Im so hoping that this is a reasonable way to get a decent air-cooled mild build Hobbit. The jailing of dos cycles ie motzig new creation is the best solution of a non slotted head for a reasonable price. No need if one is doing a simple mild build to do mods here. Stock rebuilt case or just slap on a Dr etc to a decent bottom get ahold of a bunch of 126 mm m6 or m6/m7 studs so just the Dr kit and the head needs hole enlarging. I don't know if 126 m6 studs exist but use those with a head gasket for a 44 mm ,

If a pa 1 crank then u need the pull start

If pa 2 crank go for a one way bearing.

Slap on a pipe and rejet and your temps will dip.

But again this plug when sitting but still super hot won't start. Put in a plug that's been in the freezer immediate start. So I need to get a new box of plugs and toss all these others to make sure what im testing with.

Re: Treats puch-hobbit head hard to impossible start?

If a bike won't restart after it's hot it's usually running way rich. 99% of the time

Re: Treats puch-hobbit head hard to impossible start?

Sounds rich for sure.

Re: Treats puch-hobbit head hard to impossible start?

So lean it out duh

Re: Treats puch-hobbit head hard to impossible start?

Will do jbot. First I want to buy a bunch of b8hs. Btw bu8h won't start. Any b-,hs will start and run great until restart. This is the exact same set up as I road years ago when u came up for the landquids ride. It runs bubbly rich until it hits the pipe. It follows the pipe pretty far up and has a solid mid thirties cruise. Perhaps it will go a tad faster if leaned without detonation. Again the temps were very good. I'll go down two sizes. But im kinda verical at the moment having been huddling over that bike for hours. When it running it sounds great.

Re: Treats puch-hobbit head hard to impossible start?

Emil Kniemel /

i just slapped on the slotted puch head and filed out the holes for m7. i reused my old plug and it works fine.

thank you for posting the stud length for the jianling head since i just bought one of those too and wanted to try it out but my studs are too short.

the puch head is deeper but not as wide. i collect heads too:

FFB270A2-5E39-4ED4-A714-CB06228690B0.JPG

Re: Treats puch-hobbit head hard to impossible start?

Did u snap a picture of the short thread plug in the head showing how deep it goes. I have another slotted Puch head for Athena that has a tad less thread exposed.

Ya know im using your notched variator u gave me on that red Hobbit !!

Re: Treats puch-hobbit head hard to impossible start?

> Marc Friedman Wrote:

> -------------------------------------------------------

> The red was a sharpie to test whether the head is flat. So with the two

> copper washers the motor starts initially and ran great but wont restart

> until it totally cooled. The heat fouling is probably happening still

> because the upper part of the threads aren't into the metal of the head

> so the plug I believe heats irregularly.

>

> Anyway my verdict is these heads with too much material removed exposing

> plug threads are basically unuseable. Don't buy them is the verdict.

Better test and very easy for flatness (assuming you're sanding) is just runall sanding in one direction (like up/down) then turn 90 and sand one or 2 passes (like side to side) and look to see where the original up/down scratches remain. you don't need anything extra like a marker. I do this everytime i'm sanding something smooth. When you go down to a finer grit it's a good check that you've removed all the deeper gouges from the prior grit, you just keep swapping 90 in between each size

Re: Treats puch-hobbit head hard to impossible start?

Emil Kniemel /

> Marc Friedman Wrote:

> -------------------------------------------------------

> Did u snap a picture of the short thread plug in the head showing how

> deep it goes. I have another slotted Puch head for Athena that has a tad

> less thread exposed.

>

> Ya know im using your notched variator u gave me on that red Hobbit !!

I did not take a photo sorry but it doesnt go as deep as yours. sits about flush with the hole from what i remember. the temp gauge takes up a little slack i guess.

i gave you a notched variator? lol no idea.

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