My hobbit dies when I take it off the stand

I had this issue right when I got the bike running and since have done a complete rebuild, it idles okay (no known air leaks on spray test and fresh gaskets and seals) and when I take it off the stand, it just dies. I can bump start and ride or rev a bunch when taking off the stand. Any suggestions?

Build;

Athena 70

Derbi head (br8es plug)

Boyesen reeds

Mlm 24mm intake

19mm phbg-97 main, 52 idle, 60 starter, 50 slide, w9 needle pos 3

Stuffy crank (new seals 17mm var side 15mm time side)

Yellow clutch springs

Tjt with treats ramp

Yellow contra spring

Hpi set 2.0mm btdc +-.2mm

Proma circuit

Bx40 dayco belt

IMG_20190124_195522.jpg

Re: My hobbit dies when I take it off the stand

clutch problems? bushing seized? i may be dumb but is your starter clutch seized?

Re: My hobbit dies when I take it off the stand

you're saying it rides OK if you push and bumpstart? but it dies when you're not moving? that's clutches not disengagine, either one, or you've got things pinched and binding up

if it just dies from lack of power when the wheel is down, that can be anything but on a hobbit my first checks would be reeds, compression (ring snapped on install, decomp on derbi head, upside-down piston) or seals - sometimes the inner spring popped out on install, or theyre installed too deep, or the inner lip is prolapsed out. there's that one variator side seal that people mess up, but you specifically mention 17 & 15 seals so I'm trusting that's not your problem

Re: My hobbit dies when I take it off the stand

it might be a bit lean off idle. try messing with the idle enrichment screw and raising the needle.

Re: My hobbit dies when I take it off the stand

How do you have the side cover fitting with a TJT? I'd like to do that but haven't figured it out

Re: My hobbit dies when I take it off the stand

Barry (Bob) Brown /

Not sure how you got the cover working but I dremeled a bit off the inside where the TJT hits on idle and glued a 2mm plastic spacer on the edge of the front inside the cove to keep it away from the engine and nothing hits. I can take pics if u want.

Re: My hobbit dies when I take it off the stand

> Barry (Bob) Brown Wrote:

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

> Not sure how you got the cover working but I dremeled a bit off the

> inside where the TJT hits on idle and glued a 2mm plastic spacer on the

> edge of the front inside the cove to keep it away from the engine and

> nothing hits. I can take pics if u want.

I tried spacing it out but it didn't seem like the plastic screw thing would be long enough. I'll have to take another look. Thanks

Re: My hobbit dies when I take it off the stand

It 4 strokes a bit on mid to low end with 60 idle, doesn't run well at all with a 68 idle or between. It for sure leans out when you come off the throttle due to bigger intake and smaller carb. I've also messed with needles size, needle POS, slides and main jets. So I found this setting to be a good starting base. It'll run but my issue is it dies immediately when I drop it off the stand

Re: My hobbit dies when I take it off the stand

Everything seems move freely forward and back as it should, all the springs are new and not mangled

Re: My hobbit dies when I take it off the stand

I'm guessing it's starter clutch or the clutch binding, yeah. No leaks from the can of carb clean leak test at cold start or over 200. Bike has plenty of power and pulls great when running. This is really my 1st hobbit so I'm not sure how things should look or function 100 percent yet

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