Re: Crazy Custom Frame Hobbit

Long intakes favor low rpms.

And you’re not making any power at low rpms with this kit and the pipe..

They don’t match. So wicking up is impossible.

You either have to run a shorter cutout out the side, or make a new intake that’s angled downwards and shorter and straight from the carb to the reeds.

I can see what’s happening now. The fuel mix is probably sticking then dripping along that first curve due to lower velocity from those curves.. then it drops down the top of the tube and drips right at the intake to the carb. Raw fuel dripping at the inlet of the Venturi is gonna fuck up your mix strangely and there’s no solution except for a better designed intake

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

I dig that. I'll try the angle, and after I go through the first couple steps I'll also make a short intake that shoots out the side.

I really appreciate your help and diligence with this, and am sorry I didn't just make a shorter one sooner - it's just my lack of skills and supplies has me putting it off.

Re: Crazy Custom Frame Hobbit

In the future you can make a steel intake with silver solder.. it’ll work fine, seals easy and only a propane torch needed (edited)

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

Cool yeah I'll hit up a metal shop in town. I think they're already closed today and for the weekend, but Monday for sure.

Re: Crazy Custom Frame Hobbit

Just use some old handlebars

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

If I had some I would :)

Re: Crazy Custom Frame Hobbit

Tweaker trash /

> Colin Ratcliff Wrote:

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

> Needle/seat seems fine - it's not overflowing when turned on at all -

> only when running. So it's seating, it just might be too high. I'm going

> to adjust it down.

>

> At this point, considering that I have verified that it wasn't caused by

> pooling (but pooling might be a symptom), I'm seeing the options as

>

> 1) float too high, it's flooding it because the gas is so high when it's

> open

>

> 2) something I missed with the reeds, so the back pressure is blowing

> through the jet and pushing the fuel out the bowl

>

> 3) the intake is too long, so the fuel/air mix is getting to the reeds

> after they are closed and it's on the down stroke. This wouldn't explain

> why it's blowing back, but would explain running issues and pooling. I

> find it hard to believe that this is the cause because the other intake

> I ran was at least this long, but if the other two don't solve it, I'll

> do my best to build a short intake and seal it with jb-weld or something

> of that sort.

>

> Sadly these VM20 carbs are flange mount, so I can't just pop a hose on.

Exactly

Re: Crazy Custom Frame Hobbit

You could always try another 100 carb, you have the space you could go to a vm22 which is a significant upgrade.

https://www.amazon.com/dp/B07KLG3TD9/

(edited)

Re: Crazy Custom Frame Hobbit

Tweaker trash /

Okay take the engine off the subframe!!

Mount it on the bench and get it tuned correctly with a short intake and do whatever else you can to help find the issue.

Do it or stop posting!

Re: Crazy Custom Frame Hobbit

> Tweaker trash Wrote:

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

> Okay take the engine off the subframe!!

>

> Mount it on the bench and get it tuned correctly with a short intake and

> do whatever else you can to help find the issue.

>

> Do it or stop posting!

HAHAHA maybe you should take that advice, posting your constant fucking thread hijacking bullshit

Re: Crazy Custom Frame Hobbit

Ha!^^^^^^

Re: Crazy Custom Frame Hobbit

Tweaker trash /

> JBOT Admin Wrote:

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

> > Tweaker trash Wrote:

>

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

>

> > Okay take the engine off the subframe!!

>

> >

>

> > Mount it on the bench and get it tuned correctly with a short intake

> and

>

> > do whatever else you can to help find the issue.

>

> >

>

> > Do it or stop posting!

>

> HAHAHA maybe you should take that advice, posting your constant fucking

> thread hijacking bullshit

It’s just to easy :) jk

My b, il go to the go kart forum

Walking away emoji (edited)

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

Hahah, it's a fair idea, and something I've mulled over, but getting the exhaust on it on the bench has been the challenge I've been trying to overcome.

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

@Daniel yeah, I'm thinking vm22 with the non-flange type as the next step

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

The VM22 will make it easier to test out the intake as well

Re: Crazy Custom Frame Hobbit

The polini CP is smaller and lighter. And they work better than a mikuni. I'll never go back to mikunis after using the polini.

Re: Crazy Custom Frame Hobbit

I agree with Baird the polini is better than mikuni. I prefer phbg to both, it takes a bit of swapping needles and messing with setting to get it perfect. The polini has plastic floats and the overflow lines kinda piss me off. If they made a “race” float bowl with the quick change jet bolt and a metal float for the cp it would be the best.

Mikuni seems to always work with whatever jetting they come with, least the ones treats sells. I always tell the local guys to go with the vm20 and 90% of the time they work with zero messing around. Sometimes it takes a needle adjustment and dropping the idle jet. It’s basically fool proof.

Re: Crazy Custom Frame Hobbit

Tweaker trash /

> Colin Ratcliff Wrote:

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

> Hahah, it's a fair idea, and something I've mulled over, but getting the

> exhaust on it on the bench has been the challenge I've been trying to

> overcome.

The exhaust? Dude just let it swing freely in the wind

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

I'll give it a go on the bench with letting it swing in the wind - will hit up a metal shop asap. Need new reeds first (the other block was cracked at the bolt points), so I'll make the intake this week and when the reeds get in test it all out. I'm thinking an even easier alternative to the bench is just removing the transmission portion of the engine which should give me the room to set it up and will still hold it all in place.

If I were to go with some sorta new carb that has the non-flange mount, what size should I go with? I lean towards Mikuni because I have tuned the hell out of them and have a lot of spare parts. 22mm or 24?

Re: Crazy Custom Frame Hobbit

Tweaker trash /

> Colin Ratcliff Wrote:

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

> I'll give it a go on the bench with letting it swing in the wind - will

> hit up a metal shop asap. Need new reeds first (the other block was

> cracked at the bolt points), so I'll make the intake this week and when

> the reeds get in test it all out. I'm thinking an even easier

> alternative to the bench is just removing the transmission portion of

> the engine which should give me the room to set it up and will still

> hold it all in place.

>

> If I were to go with some sorta new carb that has the non-flange mount,

> what size should I go with? I lean towards Mikuni because I have tuned

> the hell out of them and have a lot of spare parts. 22mm or 24?

Their you go! Yes remove the transmission leave the engine ( use the bike as an engine stand)

If it was me I would throw phbg on but I’m not a carb guru

Re: Crazy Custom Frame Hobbit

Daniel, they do make a quick change float bowl for the CP. Treats has em for like 20 bucks.

Re: Crazy Custom Frame Hobbit

> baird co Wrote:

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

> Daniel, they do make a quick change float bowl for the CP. Treats has em

> for like 20 bucks.

oh damn, my life is changed!

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

oh this nibbi 24mm looks pretty awesome and affordable. Any experience with them?

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

28mm is way to bloody big, right? I saw this guy and am trying to figure out what size carb to go with if I get a new one for the spigot mount:

ScreenShot2021-01-25at11.41.18AM.png

Re: Crazy Custom Frame Hobbit

28 is fine

You’ll get 30mpg tho

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

Oh shit good to know!

Re: Crazy Custom Frame Hobbit

My 24 oko gets 40mpg on a decent ported DR

I get 120miles per tank

Re: Crazy Custom Frame Hobbit

Pretty sure Bobby wasnt running a hobbit malossi kit, I think he had the mhr for the minarelli horizontal. It’s rated to like 18hp, total beast with a narrow power band that hits at like 12k. The cylinder/pipe you’re running will be best with a 21mm carb.

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

Ahhhh perfect! Good to know! Ordered! As soon as they arrive I'm gonna:

1) hook it up to the shorty intake and see if that fixes everything

2) hook it up to the long intake and see if the problem comes back.

Depending on 1 and 2, I'll decide to go with a long intake or one that kicks out the side, and if 1) doesn't solve it I'll look for some other problems

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

Alrighty! New carb, new intake, v force reeds. Issue still seems to be there. Am I crazy?

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