Molkt Carbiy, what's the go?

[unit_mx]

I've tried searching the forums for any threads regarding Molket carbies. There are none to my understanding. Im looking for a new carb set up and have so far come across some preety decent PE and VM carbs from the states. But im curious to know about the molket carbies PIMPIT sells?
Has anyone had much experience with these carbs?
Are they hard to dial in? How far are they from spot on in stock settings?
What model carb are they based upon , they look similar to Keihin PE26mm?
How do they run?

Im quite intrested in these carbs , they are sold exeptionally cheap in comparison with the OKO carbs. Just wondering whether its worth the trouble purchasing one of these...

I also had my eye on a Kitaco 26mm Carb kit including what appears to be a mikuni VM26mm carb , manifold , flange , throttle and cable as I can get one reasonably cheap at $250 new

If anyone could assist me in the molket carb enquiries it would be much appreciated!

 

[tubes380]

apparently there ok, hard to tune though compared to oko and other carbs from what i have read

 

[TardTerror]

yeah i have heard the same thing as tubes,
they come stock with most of the yx150 stuff so maybe try some american forums as they have a fair few yx's going now

 

[Maylands Performance]

Hi unit_mx
The Molkt carbies are supplied STD with most of the current crop of 150cc pitbikes.
Out of the box the Molkt carbies seem to be either run Sweet as,or leak fuel,cause hard starting and run ragged as !
We have had to Bin quite a few of them so far this year!
Myself I wouldnt go out of my way to fit one as an upgrade carby.
For a small $$$ outlay I would rather fit an OKO 26mm or a re-jetted common old Mikuni "30mm" carby !


Cheers Brian

 

[powerfit]

If you do go with the molkt on the 150cc I highly recommend
changing the Main jet to 100 and needle clip position to one position lower as this carbie comes with a fairly rich jet setting standard

This combination has been dyno'd and managed to gain and extra .5 - 1hp midrange to toprange on the 150

As far as the carbie is concerned I have had a couple of these and 1 runs sweet with no problems and the other has had all sorts of problems, spluttering on idol and WOT, fuel release screw jammed, bascially DOA

The slide is a little larger than your 30mm mikuni and the intake has some extra funnels but overall the carbie will not greatly outperform the 30mm mikuni

 

[unit_mx]

Hi unit_mx
The Molkt carbies are supplied STD with most of the current crop of 150cc pitbikes.
Out of the box the Molkt carbies seem to be either run Sweet as,or leak fuel,cause hard starting and run ragged as !
We have had to Bin quite a few of them so far this year!
Myself I wouldnt go out of my way to fit one as an upgrade carby.
For a small $$$ outlay I would rather fit an OKO 26mm or a re-jetted common old Mikuni "30mm" carby !


Cheers Brian

I know you have had alot of experience with the standard Mikuni carbs , I've tried to jet mine using different needle tapers , mainjets and clip positions but have yet to find a decent combo?
It would be of tremendous help if you could list the carb settings you use? I've herd the 102.5 main , needle on the 2nd slot from the top and fuel mixture screw 2 1/2 turns out works good , but whats your optimum setting?
I've got a ported and matched DC26mm intake manifold , Unifilter , 32mm exhaust header , NGK CR7HSA spark plug , 1/4 throttle etc on the standard carb?
I tried a crf100f keihin PD25mm carb but the float bowl seal expanded when I removed the bowl to change out the main?

So far I've had no real luck with Carbies and am reluctant to purchase another one at this stage. I know jetting takes time but I know a few of you guys on here have ironed it all out with these standard Mikuni's and am curious to know how well they run? Before purchasing a new carb.....

Cheers

 

[DDR200supermotard]

hey man personally i like the keihlin and oko carbs and you can get them off ebay for about 125 i think which is really good. thats the way i would go and from what i have heard about those molket carbs they need a lot of time tuning.

 

[Cactus Jack]

I've previously figured out that what Brian from Maylands is saying is spot on ...... the MOLKT carbs getting flogged off cheap are most likely to be problem carbs removed from customers bikes ..... and they smell of fuel too ..... But that can be a good thing ..... if you can buy a MOLKT cheap then sort it out you'll be laughing ...... From what I can gather it seems that it's absolutely critical to get the float level set spot on for those carbs to work right ......

Anyway , talk about coincidence .... I sift thru sites and save any interesting info and just last night I was reading this thread on PM :

More Molkt Junk Jetting - Planet Minis

 

[daimojay]

i bought one from ebay, a 28mm for my gpx when it was stockish (high comp piston, irk and ethanol blend) ran a 22.5 pilot and a 107.5 main and it ran sweet. but on normal pump fuel i had to step it down to a 97.5-100 depending on temp etc.

admittedly it did leak out of the bowl gasket, but i just cleaned it up and siliconed it and never had a problem

 

[chinaman]

Hey all, What hight should the float be set at? I saw somthing on here once before about correct float hight. Do different carbs have differnt hights I got a molket on my other motor (yx150) and it wont rev right out nearly stalls when i try to rev it out. I checked everything i can think of. Resistance of all my coils swaped my cdi, checked all my electrics and my valves. Im starting to think it could be the carb. I already had that apart to and blew out all the passages in it and jets out with compressed air. Do you think it could be float hight? Plug dosent look lean either and it didnt do it when i first got it any ideas anyone? Sorry to jack your thread man.

 

[daimojay]

sounds like the jetting to me. the float should sit level when you turn the carby upside down.... and try putting a bigger jet in the carby and see if that helps?

 

[chinaman]

Yeah well thats what I thought at first so I played with the needle going richest and leanest. But then when i thought about it it was running sweet when i first got it so that makes me think somthing else. The only thing in the carb i didnt check was the float hight. Could this cause it?

 

[1fifty1wheel]

i'm not a fan of the molkt that came with my 150, have settled with an oko 28 after collecting oko 26,28&30mm to play around with.
you may remember the carb dramas at angle thread i had a while back.
the 28 has brought the bike right out there, easy to tune and uses keihin hex jets (the sort ones). the only problem i've heard is of the poor quality hardchrome (or lack of) on the slide, reducing its life. but for a sub$100 carb who cares?
the manifold and adapter used if you purchase a kit has a much smaller ID but both can be easily match ported.

 

[Cactus Jack]

Molkts are only really 24 mm I/D thru the venturi when you measure them with a set of verniers ....... the OKO's are precisely the size they are rated at ....... so a 26 or 28 OKO are both bigger carbs .......

The Molkt I bought off ebay had the float bowl seal cocked up so that it would have leaked fuel if tilted and the throttle cable seal had the top torn off it .... A leaking cable seal will make the carb suck air and run lean up top plus not hold a constant state of tune so people with Molkts should check that out and make sure there's no air leaks anywhere ........

 

[themountain]

Why all messing with that crapcarb?? get a decend Keihin...end of story!!

 

[Cactus Jack]

To experiment with mountain .... If you never , ever , have a go .... you'll never , never , ever know ....

I've got 26 and 28 mm OKO's , a 26 mm Miconi , two 24 mm Molkts (one bought off ebay for $50 and the other came stock on the DHZ 150 bike) , a VM-24 Mikuni , a VM-28 Mikuni , a PE 28 Keihin , two 22 mm Mikunis (aka "25's") , a 22 mm Keihin and a 20 mm Keihin .....

But I've also got 8 motors to frig around with .... and like 1fifty1wheel says ... they're so cheap that it doesn't matter ... you just use what you find works best , then sell what you won't be using .......

 

[unit_mx]

Ok it sounds like im going to go a few alternatives.
Im looking at getting one of the following carbs:
- Keihin PWK 28mm flatslide
- Keihin PE26mm roundslide
- Mikuni VM26mm roundslide
- Mikuni VM24SS (Or just VM24) 24mm round slide

I've also found a 26mm Mikuni T1 (Never herd of?)

Also:
- Oko PWK28mm replica carb
- Oko VM26mm carb
-OKO Vm24mm carb

My basis of purchase will be on:
- Performance (1 priority as I can get a shop to tune it up) , I prefer bottom end power than top end , so mybe a smaller carb 24mm perhaps?
- Ease of tuning (2nd)
- Durability ( Questions OKO carbs??)

With the VM type mikuni's I've noticed there is two different styles of choke lever. The lever style and the pull out button style. I looked around on Planet mini's and there was nothing but Thumpertalk had a thread about it. Apparently despite being almost a identical carb they both run different pilot jets to each other?

Also alot of these carb's are from 80/85's and 60/65's including the VM's and the PE's and PWK's. Im most likely going to buy the carb from the states as the choice is much larger!

Also I've noticed an evolution in carbs from the earlier 80's and 60's to the 85's and 65/60's but are still refered to as VM's. No difference in name but was wondering what would be the main upgrades , as I've noticed the choke lever is the main difference?

Also what is the benifit of a flatslide carb compared to a roundslide carb? And why is the vm26mm oko kit from dhz worth more than the pwk28mm kit (oko) from the same place???


I just bought a genuine SDG pipe set up from the states too , it appears to be decent quality with what looks to be a mandrel bent header with a expanded muffler fitting and the muffler clamp is welded on so there is no clamp to strech. Has anyone had experience with these pipes?

My current set up is a 140cc lifan , ported and matched DC26mm manifold , China rev box and NHRC 1/4 throttle if it helps....

Would a trailbikes rev box offer better performance compared to these china rev box's and work better with a decent carb setup?

Sorry about all the questions ...

 

[themountain]

To experiment with mountain .... If you never , ever , have a go .... you'll never , never , ever know ....
..

right , but most of the forum users are mostly too retarded to change the wheels , so to get some advance from a carb change , why the heck don´t use something its already proven

 

[unit_mx]

Don't worry im not afraid to experiment a bit , I've tied different carb's in the past , but im not exactly ballin in cash I just spent $2k getting a complete motor rebuild for my 250f and dont have much change to buy 3 or so carbs to muck around on?
Not really mechanically retarded , willing to give something a go! I got a vespa et4 oil cooler on my mini , don't see to many of those getting around?

 

[Cactus Jack]

right , but most of the forum users are mostly too retarded to change the wheels , so to get some advance from a carb change , why the heck don´t use something its already proven

I know a lot of readers aren't too skilled with mechanics or tuning ..... that's exactly why I go out of my way to explain things in detail and supply heaps of info in the hope that some of those people might find it helps them out in some way .... Also , we have to make Mini Riders an interesting place to visit A stack of people will have bikes with MOLKT carbs and simply can't afford to just get rid of them and buy a higher priced carb kit that you STILL have to sort out anyway ......

The info below was typed out earlier :

Selling your MOLKT new (if your bike comes stock with one) without putting fuel thru it and buying a better carb kit that comes supplied with an assortment of the proper jets for fine tuning would most definitely be the best route to go for anyone who hasn't tuned carbs before ..... BUT they are pretty expensive to buy over here and are STILL largely unknown about ...... so people are reluctant to fork out for one of those types of kits without knowing it's going to work better than the carb they've already got ....

I think the problem is that carbs work with smaller main jets over here yet the carb kits come with far bigger jets ...... so you'd still most likely have to toss all the jets and part out for new smaller ones that work at close to sea level .....

What I have always done in the past to find a starting point for jetting is to look for a Japanese 4 stroke bike that has similar cc capacity and carb size compared to the carb you're using .... then find out what pilot and main jets it's running and go from there ......

In the case of a 140 to 150 engine .... an XL 175/185 runs a 26 mm Keihin so you'd look up the jet sizes that Honda has used and you can bet your nuts that they'll work nearly spot on right off the bat ........ And I've found that things work totally different to what people THINK .......

ie early SL/ XL100's and 125's (road /trail bikes) both ran the same carb ... a 22 mm Keihin .... when you check what jets they ran ...... you find that the 100's ran #110 main and #38 pilot as stock .... yet the 125's ran a #100 to #105 main with the same #38 pilot ..... I tested my XR's 22 mm Keihin on a ported 110 Loncin and found the #105 jet to work great !

For racing and high performance with XR75's , people fitted the 22 or a 24 mm Keihin .... even back then ... the 22 was the most popular choice because you could find used ones in excellent condition off a 100 or 125 for a reasonable price .... as far as I know , NO Honda single used the 24 mm Keihin so they were ridiculously over priced by the bike shops to the point that you simply wouldn't pay it .....

Anyway ...... I did thorough stop watch testing on both stock and worked XR's fitted with 22 mm Keihin carbs and found the #105 main and #38 pilot to work the absolute best all round ....... they ran clean , crisp and snappy with those jets .... no bogging , coughing , farting , spluttering or over heating even when being ridden fast or slow all day long .

You only have to check out carb rebuild kits for various sized Honda 4 stroke engines to see that the jet sizes don't vary too greatly with big cc differences .... :

'73-'76 XR75 .... (#38 pilot #100 main in a 20 mm Keihin)
'77-'78 XL125 .... (#40 pilot #98 main in Keihin PD65 carb / trail plonker)
XL/CB125 ......... (#38 pilot #100/#102 main - 22 mm Keihin )
CB125S ........... (#38 pilot #95 to #110 Main (hi-po road engine run at sustained high revs on highways ... so it can lean burn at times and needs to be richer to stay cool)
140/150 China engine w/ 26 mm carb would be somewhere between these !!!
XL 175 .............(#40 pilot #110 main in a 26 mm Keihin)
XL 185 S .......... (#35 pilot #102 main in Keihin PD carb)
80-84 XR200.......(#35 pilot #115 main in Keihin PD carb)
'76 XL250 ..........(#45 pilot #125 main)
'73-'76 XL 350 ....(#48 pilot #130 main)

The above jet sizes were worked out by Honda engineers thru R&D testing .. so they're extremely reliable starting points Simply convert the Keihin sizes over to Mikuni sizes for carbs that use Mikuni jet sizes .... for carbs with weird unknown jets it'd be simpler to buy jet drills ...... especially if you have a several bikes to tune .... unless you can find out what Mikuni or Keihin jets they match ......

Most VM 26 Mikuni /OKO 26 round bore etc carb kits you can buy come stock with dorky giant two stroke jets .....

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