Going to try the new Hummer G4

Mini Dirt Bikes & Pit Bikes Forum

Help Support Mini Dirt Bikes & Pit Bikes Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Well it's official - I got an answer from both Atomik & Dreamrider to say that the Hummer G4 is temporarily off the market, awaiting the release of a new model.

According to Atomik - the new model will have an optional lights kit!

Release is set for Spring/Summer - so there's a bit of a wait!
 
Hmmm - I wonder if this thread has made the Hummer too popular and they're getting more money by only selling to retail? I notice all the Hummers for sale in shops have either the Atomik or Tomahawk Import brand - rather than some generic import graphics.
 
Hey boys - I wasn't expecting the new Hummer until Spring - but Atomic have the first one on E-bay now.

NEW ATOMIK KUDA PRO 250CC PIT DIRT BIKE MOTOR THUMPSTAR - eBay Other Trail Bikes, Trail Bikes, Motorcycles, Cars, Bikes, Boats. (end time 29-May-08 19:30:00 AEST)

The specs look great - although it's strange they have changed over to a Loncin 250cc OHC engine.

15.5Kw is starting to get useful on a stock engine though - and all the fruit looks as good or better than the previous model - plus of course you get the lights!

Only three questions boys! How will it perform - what will it cost and who's going to get one first Ha Ha.
 
hi guys just seeing if someone can help me out i have a hummer 250 and i have put a 1.5mm main jet in it with a pod air filter and a hotter plug but now i have good power down low but when i get up in the revs it is braking down like it is runing out of fuel or spark is braking down it is not over fueling because there is no smoke at all its more like it is leaning off i was thinking that now the float level might need adjusting to keep the fuel up to it as well when i free rev it i can hold it flat out and it don't rev all the way out the same time i picked up on this i was in a lot of wet mud and water the bike was covered can some help me with some ideas on what might be going on with it
 
Mate you've got a lot of new stuff going on there all at once - which always makes it difficult to diagnose faults.

The first thing I'd do is go back to the original plug - just to eliminate one of the variables.

If a bike runs rough at high revs, the mixture is usually too rich. You will notice this effect if you leave the choke on when the bike is hot.

Depending on where you have set your carbie needle, you can try adjusting it to make the mixture run leaner or richer (as the case may be).

If that doesn't work, you need to check that your new filter is letting the air through O.K. Be careful when applying filter oil - using too much can restrict air flow.

At the end of the day, you can always have your carburation analysed on a machine - which will give you a definitive answer for only a few bucks.

At the end of that process, you may discover your new jet isn't optimum for the current set-up - but at least you will know!

Once you get your fuel/air mixture working and the engine running O.K. - then you can try a high performance plug

The rule is - one change at a time - optimize performance after each change.
 
Hey Guys
I have noticed some people asking about jets,
I replaced the secondary jet in my Kuda pro when i replaced the muffler with the carbon fibre pipe and i just took the jet as a sample to my local bike shop which is easy as the carby is a Mikuni nock off! so in this case i went to a 110 on the secondary jet, after my crash i got a new double covered pod filter off eBay and i put that on the bike and it was lean as hell so out came the carby again to replace the primary jet which started off as 39 standard, again visited my bike shop and with the old jet as a sample i got a new one but the shop only had a 42 and a 48 so i got both and after putting the 42 in i found this jet gave me the pefect tan colour required.
So i just can say take your jets with you as samples but any bike shop should be able to help as the carby are Mikuni nock off's
 
hi guys thanks for your help my carb is a 30mm keikhin the main was a 108 and the primary is a 36 i used a 1.5 jet drill on the main do you think this might be too big i had the needle set on the bottom grove i moved it to the center it did not seam to do much to fix it the air filter is sucking as i can hear it as whit the old air filter it had no hope i put the filter on first and it had big flat spots that is why i played with the jets now it is just doing my head in
 
I'd take Weedgee's advice on jetting.

I didn't realize he'd gone for a pod filter as well as the new muffler - but seeing that he has, the jet set-up he's used should be in the ball park for you.

I'm sure Weeg will give you a precise run down on his settings if you drop him a line.

Also the following link will allow you to download a tuning guide from Mikuni.

It's the VM series you want.

Mikuni American Corporation

This gives a pretty good account of how to get the best out of your set-up. Even if you have a different brand of carbie - the thory will still be applicable.

Although the hummer specs say that a 30mm Mikuni is used, it is actually the VM 26 which is most commonly used.

New jets for your carbie should be available at peanut rates.

Good luck with the project.
 
Hey rod
Sorry i thought i had mentioned the pod filter? anyway i bought it off eBay and i liked this one becuase it has the nice tight foam inner but a cause removable out skin which i thought would be good for cleaning real quick. And where i ride there is no water for crossings more than ankle deep so i think it should be ok and hopefully add some more grunt. I still have to put the sprockets on too so maybe this weekend after the ride i will do that.
 
No worries Weeg,

Yeah - pod filters are easy to look after and maintain. Unfortunately where I ride, they would gunk up in two minutes flat.

I had to keep the air-box and mod it up to be bullet proof instead.

I have to say it worked well - and the bike has survived a couple of drownings! The only down side is that it's a real pain to dismantle and clean, but then it keeps me busy and away from the mowing on week-ends - Ha Ha!
 
hi guys thanks for your help i took the carb into the bike shop today and he is all over it the main jet that i had was to big that is why it did not rev up high so he is having a play with it for me
 
seen thie blitz bike at atomik when i was picking up the missus thumpstar. its a big bike about the size of yzf450 just wondering if its strong? Up next the kudas and fury it was a monster i thought it had a 400 in it.
 
Hi Boys - just got back from a business trip to India and took a little time to visit the Royal Enfield factory whilst I was in Madras.

I work for a Perth engineering company - so there are a lot of bike enthusiasts around the place. I'm taking orders for the boys on my next trip and will ship some bikes over to Perth in a container. For three grand you can get a 350 or 500cc classic. which has only had disk brakes and electric start added since the 1960's. In black & chrome they look really shmik and apparently are really reliable old thumpers - check out the web site:

Welcome to Royal Enfield Motorcycles | Motorcycle India

Theres also a US and Brit site you can link to (see top RH corner of web page) and they show all kinds of different models made up for export.
 
seen thie blitz bike at atomik when i was picking up the missus thumpstar. its a big bike about the size of yzf450 just wondering if its strong? Up next the kudas and fury it was a monster i thought it had a 400 in it.

They look bigger because of the water cooling - where the radiators add quite a bit of bulk.

I don't know if I'm ready to accept a China with liquid cooling yet though!

Like you say, the Chinas are getting better all the time - but liquid cooling adds another layer of engineering complexity, together with higher design and materials technology requirements. Then there's always the problem of stacking your bike and putting a hole in the radiator - especially when you're stuck out in the bush miles from anywhere!

I've noticed that even David Knight (world enduro champ) has pulled out of events with buggered radiators - and he rides for KTM!

I think the current trend for water cooled dirt bikes may be a passing fad. The concept may hang on with motorcross bikes (where speed is everything and you've got a mechanic at the track) - but there are too many potential problems with it for bush bikes.
 
I've been having a look at the new Kuda Pro specs

Besides a change over to the Loncin OHC engine, extra bling and lighting kit, the drive has been updated to a heavier 520 gauge chain. Looking at the overall length, I think they've also increased the length of the swingarms, which will make the bike more managable up steep hills.

The ligting suite and instumentation looks pretty OK - so I'm wondering if there would be much to do to make this bikea registerable dual sport? I might write to Atomik and ask.

All in all it looks pretty good on paper - anyone who buys one please write in and let us know.
 
Last edited:
so I'm wondering if there would be much to do to make this bikea registerable dual sport?

By dual sport do you mean road reg as well?
I'd definitely be interested in that.
It'd be handy for a quick run on the road around to a friends place etc.
 
Back
Top