Re: Hobbit.... and we're off!

I’m telling you it’s the springs.

It will feel lean but it’s just engaging where you have no power at all so it dies

That’s why it revs in the stand ok with the rear wheel spinning

Re: Hobbit.... and we're off!

Alex Hedrick /

> JBOT Admin Wrote:

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

> I’m telling you it’s the springs.

>

> It will feel lean but it’s just engaging where you have no power at all

> so it dies

>

> That’s why it revs in the stand ok with the rear wheel spinning

That does make sense! Its got no power off idle and thats where the clutch is engaging due to the springs.

I know I'm real close on the tune carb/timing wise. I need to get it put together more so I can ride it and really start tuning it under load.

Re: Hobbit.... and we're off!

Does it idle off the stand?

Re: Hobbit.... and we're off!

Alex Hedrick /

> Marc Friedman Wrote:

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

> Does it idle off the stand?

Yeah! Idles fine! Just has a bog spot at about 1/4 throttle and down.. basically it bogs if I rev it off idle.. but I can get past it and it revs to the moon

Re: Hobbit.... and we're off!

Like Jbot said....clutch spring. Clutch engages before it makes any power.

Re: Hobbit.... and we're off!

Dirty30 Dillon /

You have a huge carb and huge pipe, on a hi Ron kit and low clutch stall, you're stalling the ports.

Also, you are def jetted very high, considering the powerjet which basically only adds at WOT.

Re: Hobbit.... and we're off!

Alex Hedrick /

> Dirty30 Dillon Wrote:

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

> You have a huge carb and huge pipe, on a hi Ron kit and low clutch

> stall, you're stalling the ports.

>

> Also, you are def jetted very high, considering the powerjet which

> basically only adds at WOT.

I get that.. im not even on the power jet, or close to it at 1/4 throttle. but I am able to bring it on no problem..

I did port the cylinder and raise all the ports .0300" and did some port shaping. Also decked the cylinder .0350" I know the cylinder can use the big carb/pipe. v force reeds matched and flowed to the intake I made up. Everything flows and breaths proper like.

Definitely not acting like a big carb issue. Just a lean bog plus a little of what jbot was saying.

I will report back tomorrow or something

Merry Christmas everyone!!

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Re: Hobbit.... and we're off!

Alex Hedrick /

Alright ladies.

Got brake cables cut to length and set up.. throttle all set.

Took it out for a ride,

Cool it feels good.. but.

Stock rear spring, tjt front pulley with 2.5g rollers. I know.. they are light as fuck. But its what I got right now...

Anyway, its actually not half bad.. powerband hits and it stays there thru what I think is the full variation,( its dark and I can't see shit)

Maybe doing around 30/40mph or so.. everything feels good, then boom.. its like its over variating or stretching the belt and bogs down.. mind you. Im at maybe 8k rpm..

What the fuck.. lol

JBOT.. where you at?

Re: Hobbit.... and we're off!

Tell me the entire trans setup (edited)

Re: Hobbit.... and we're off!

Oh I see it ok

Re: Hobbit.... and we're off!

Yeah tjt can not run with the stock rear without modifications. Did you mod for max closing?

Only once this is done can you run a tjt without damaging anything.

As well you’ll need a rumpus plate if you want to use the stock spring. Or just get the red spring for stock hobbit rear pulley and use the stock tjt plate (edited)

Re: Hobbit.... and we're off!

Alex Hedrick /

> JBOT Admin Wrote:

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

> Yeah tjt can not run with the stock rear without modifications. Did you

> mod for max closing?

>

> Only once this is done can you run a tjt without damaging anything.

>

> As well you’ll need a rumpus plate if you want to use the stock spring.

> Or just get the red spring for stock hobbit rear pulley and use the

> stock tjt plate

I did not mod anything on the drive train.. other than the tjt and ramp plate..

Is this max closing mod for the rear? Brief explanation?

I can rev it out and watch the rear pulley fully open, and the tjt is still trying to close.

So rear pulley is hitting its limits.. tjt is still variating stretching the belt.. not an insane amount, but I can watch it happen on the bench and im not down with it..

Re: Hobbit.... and we're off!

Look up modifying hobbit pulley you fucking newb

Re: Hobbit.... and we're off!

and yes stock pulley has shit for travel.

Make it close more, thus more travel.

Then if you set the belt at max height in the rear pulley, you won’t stretch the belt or break the rear shaft right away

Re: Hobbit.... and we're off!

Alex Hedrick /

> JBOT Admin Wrote:

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

> and yes stock pulley has shit for travel.

>

> Make it close more, thus more travel.

>

> Then if you set the belt at max height in the rear pulley, you won’t

> stretch the belt or break the rear shaft right away

Hey now.. i am a noob..

I know about it and what the mod does, I just don't know the juicy details.. haha I didn't want to do it.. ive been lazy..

So I know light spring and light rollers it becomes really touchy to dial in..

I hear its better to run stiff/heavy

(red hobbit spring)

And anywhere from 9 to 14 gram rollers..

Re: Hobbit.... and we're off!

Alex Hedrick /

I've got a feeling ill be throwing a gy6 rear pulley on it at some point..

I know you can't really get much more out of the stock rear.. plus why the hell not..

It runs, motor pulls really good, max water(NOT PLUG) temp i got was 170°f, it stops good, time to finish it out and paint shit i guess.. I hate this part..

Re: Hobbit.... and we're off!

There’s gonna be something available really soon that is 100% baller. That’s all I’ll say in this matter

Re: Hobbit.... and we're off!

You can get a ton of performance out of the stock rear pulley though.

Look up the progressive dual spring mod.

That allows a second spring to help on the higher positions which tend to collapse the pulley. I did that a lot before other options were available

Re: Hobbit.... and we're off!

Alex Hedrick /

> JBOT Admin Wrote:

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

> There’s gonna be something available really soon that is 100% baller.

> That’s all I’ll say in this matter

Uh oh.. I like the sounds of this.... Ive had a feeling something has been in the works.. its been too long without something good for Hobbits drive train..

I'll check that out!

I think for now my only issue is the rear pulley cheeks hitting its limits and the tjt really pulling on the belt causing lots of friction making it bog out.. ill play more tomorrow!

Thanks for the tricks man.. I like learning new shit!

Re: Hobbit.... and we're off!

I have a gy6 rear pulley. It's yours for what I paid plus I have the correct malossi plastic base to keep a spring perfecto. Cheetah chrome did a few pulleys for me so this is a spare. I also have a stock pulley that needs the cheetachrome treatment. It's on a complete sub that I need to maintain if my water-cooler needs a chp look over to register. I've become mega lazy . So anyway if I want the gpy6 or what ever it's codename is remember it variates in a direction opposite stock...I'm not saying thats an absolute no...I just decided that I didn't care for it's performance BUT I bought but didn't install the malossi gizmo which purportedly cures all man's and moped ills. Jbot bro cut me some slack even if you are feeling unhinged. I've been worshiping at the altar of mountain bikes and just putting around to my buddy Jerry on my underpowered bravo because ...it likes 20 mph. And it's suburban davis. But I'm following even if you think I'm totally in error. Alex please give us some feedback on the frame mods and the ability of the front end to stay down and be balanced in typical town and out in the country roads. I've got my water-cooler on a completely stock geometry setup thinking maybe the guys who designed it maximized handling. They did make performance motorcycles and wanted the least amount of mayhem , probably designing them primarily at most derestricted ( usa 30 mph) plus by then they were aware of simple speed mods and probably designed a bit towards that no different than today's pickup trucks.

The above is all conjecture.

Re: Hobbit.... and we're off!

Marc you ignore all sorts of variables.

Longer Wheelbase always makes it harder for the front end to come up. But seat position and motor strength and position of the belt in the front and rear pulleys and clutch engagement are all much more responsible for uncontrolled wheelies. My front end comes up on my 4 inch stretched hobbit at takeoff if I let it. Every front end should come up if youre giving a sudden burst of power that overcomes the front end weight and seat position leverage.

If my built 70cc hobbit had the stock length it would be barely rideable without adding weight to the front end or leaning over the bars at every takeoff. My built 50cc would lift its front wheel fast on the stock stance to the point that I had to change the tune in order to ride it.

Your obsession on stock length being somehow better or more stable is mega wrong on its face but whatever. I’m the unhinged one here I guess.

If Alex’s seat was right over the rear wheel the front end would come up bad even stretched. Why? Cuz the front is light due to the riders weight being over the back wheel where it should never be unless you are stunting. I really don’t think you understand physics.

I have one incredibly fast light short bike. Its really scary. But the front wheel doesn’t lift. Why? Because I moved the seat way up so all the weight is planted in the center and there’s no way the engine can overcome it to throw my fat tits off the bike. It’s extremely stable, but not because of the length. Its because of the weight distribution. If I stretched it it would still be just as stable or more with the seat further up. (edited)

Re: Hobbit.... and we're off!

Alex Hedrick /

Yo marc. I sent ya a message!

Alright.. jbot is spot on.. hence half the reasoning for stretching it.

Move the rear end back about 7/8 inches.. whatever it was. Damn near keep the seat position just better seat..

Better ratio of being centered over both axles.. sure the rear to front is like 60/40, maybe more..

One thing that's forsure is when it gets in the powerband, I can still feel the front end lighten up on me.. not uncontrollable or anything.. but I just feel it.. I can lean forward just a little bit and problem solved.. if I kept the wheelbase stock.. I know for a fact that it wouldn't even be rideable. (Like jbot said)...

So all in all, the subframe stretch is sweet.. handles fine. Goes straight. Yeah. I dig it!

If you want to do it yourself and fuck it up? Hell yeah do it, especially if you plan to make it a total ripper.

-'OUT'-

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Re: Hobbit.... and we're off!

Alex Hedrick /

You guys are nuts.. its pretty damn sweet!! Wish I took more pictures but I was in the zone.. also.. hacked apart a rear pulley for the taper.. ill make another one soon but this one actually came out sweet! Nice n straight.. had a little wobble to it but I was able to bend the inner pulley check around and get that out. Took it for a rip and hell yeah.. stock gy6 spring 18 grams of rollers.. still stock clutch prings.. waiting for new ones to come. But its sweet. Variates smooth and full variation at that!

More to come soon!

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Re: Hobbit.... and we're off!

Alex Hedrick /

More photos...

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Re: Hobbit.... and we're off!

Alex Hedrick /

Teflon tape worked great for centering the tapered big in the gy6 bore. Ran it on one of my dividing heads with an indicator, only .0015" runout which, if you asked me is better than stock. Maybe.. either way. Its sweet. Now.. welding to the factory weld on the gy6 was a total nightmare.. shit was nasty but I packed it in there and got it done. Its solid!

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Re: Hobbit.... and we're off!

Alex Hedrick /

Now I will be making the third bearing support work with the gy6, just need to get to my work so I can turn down a thing to shove in there and make work, other than that its pretty much good to go.. swap out the bolts holding the bearing in for some cap head bolts to get that clearance back and there it is..

Lots more to come!

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Re: Hobbit.... and we're off!

You’ll find out the hard way.

The third bearing will help but you’ll still break off that inner cheek I bet. Gy6 pulley is hot garbage, and also meant for 4t, the angles are all wrong

But I applaud you on fighting against what we’ve all already discovered.

Re: Hobbit.... and we're off!

Alex Hedrick /

> JBOT Admin Wrote:

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

> You’ll find out the hard way.

>

> The third bearing will help but you’ll still break off that inner cheek

> I bet. Gy6 pulley is hot garbage, and also meant for 4t, the angles are

> all wrong

>

> But I applaud you on fighting against what we’ve all already discovered.

Haha why thank you!

I know, im a learn it the hard the way kind of guy..

But im determined to make it work. And when it doesn't, ill go all out and swap out everything to er3 front and whatever the rear is lol I forgot..

But so far so good! Ill post a video real quick.. its kinda of a shitty one so shh....

Re: Hobbit.... and we're off!

I am having some issues with a Start V and bogging. My initial inclination was carb mistuning but after reading this, I am thinking it could be a variation issue. This is my first variated bike.

Start V with 65 cc metrakit, TM24 (15 idle jet, 165 main jet, middle needle position, 5n13 needle) 6 gram weights, 16/33 gearing, removed starter clutch, stock contra and variator. Rk replica huge moped pipe w/ black baffle. Malossi reeds. Timing 1.8mm. No air leaks with leak down test.

The bike idles and revs without on the stand without issues. The bike is 4 stroking with acceleration - a lot at 1/2 to WOT and less frequently at WOT. The bike accelerates decently until 1/2 throttle then there is a lot of hesitation and losing of power and spitting gas.

I have tried leaning the main down to 115 and needle position but this makes the bike run worst and there is still a lot of 4 stroking in the mid range. The plug looks to be on the richer side but not bad. The head temps hang around high 200s. Leaning up the main jet did improve the spitting of gas.

How can I tell if it is carb tuning or variator tuning?

Re: Hobbit.... and we're off!

Alex Hedrick /

So this was before I got the inner check wobble out of it.. (came that way from factory)

its much more smooth now and no bad vibrations that I can feel.

I got a heavier spring comin as the stock one seems way to light.. and some more roller weights to play with.

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