Going to try the new Hummer G4

[Ingleburn]

A lot of Chinese bikes have different sprockets - so you need to be careful.

The Hummer (or Kuda) has a 4-hole sprocket with 6.5mm centres.

A good choiceis a 48 tooth rear sprocket, matched to the existing 15 tooth front sprocket (you should be able to get one from Atomik - or if not, then Tomahawk definitely carries one)

The other option (which is what I did) was to go for a big 56 tooth rear sprocket - matched to a 16 tooth front sprocket, giving you a drive ratio of 3.5. These two sprockets I got from Bataycan in the Philippines - and here's their web-site address:

eBay Store - Zongshen performance: Performance parts, Appearance and beauty, Hausmotors

By the way, these guys also sell the hot Zongshen racing engines and carbon fibre exhaust systems.

The above combination of sprocket will cut your top speed down to just over 100kph - but you will get there in a real hurry and have plenty of torque to climb hills and plough through the rough stuff - a very worthwhile mod.

Cost for this mod - Option 1 around $35, Option 2 around $60

this might be helpful

 

[rodbox5]

Hi Dropbear - it all depends on which dirt bike you have bought.

If your bike has a hummer type sprocket, then it will have 4 mounting bolt holes with 65mm between hole centres. If this is the case, it will also be set up for 428 gauge chain.

If on the other hand you've bought a Jap or European bike - then each make has their own sprocket mounting design - with varying amount of mounting bolt holes. Most Jap and European dirt bikes bikes (250cc) - will use 520 gauge chain.

With Hummer type sprockets, you can purchase them up to 48 tooth from either Atomik Sports or Tomahawk on e-bay. For larger sprockets (up to 56 tooth) you will have to look at a company like Bataycan in the Philippines. These are good guys and they sell some very speccy gear for the Hummer - Their link follows here:

eBay Store - Zongshen performance: Performance parts, Appearance and beauty, Hausmotors

These guys also do the front sprockets (up to 17 tooth) - which means you can set up just about any drive ratio you want. On a Hummer - I'd reccommend a 16 tooth front sprocket and a 56 tooth rear.

For chain - I'd reccommend a DID 428 NZ black & gold chain. These are sometimes offered on e-bay at bargain prices - or you can get them from your local dirt bike shop - in which case expect to pay around Aus$75.

The DID Spec chart is here:

Specs

These are really good chains - and are what you need. In my opinion 428 gauge is a little too small for a 250cc - so you need to get the best quality chain you can. The Chinese chaims that come with the bike will typically only last a few rides.

Hope this helps.

 

[Ingleburn]

Hi Dropbear - it all depends on which dirt bike you have bought.

Yeah rodbox looks like he bought the kx from dreamrider. Looks similar to the hummer so should take the same parts. This is the 1 i was thinking of buying so be interested in how it goes

 

[dropbear]

Hi rodbox5
Yes its a 2008 250 kx tomahawk form dreamrider its a good bike for less than 1k I have ridden about ten times just changed the plug as it was missing above 3/4 throttel take out later today and see if this has fixed the problem

 

[Ingleburn]

when youve got time want to throw up a pic or 2.

 

[matty_02]

Hey dropbear and rod,

I gave an update in the thread i started on buying a bike for around 1k!!

Dropbear, i ended up purchasing the same bike as you from dreamrider. The Tomahawk KX, i liked the look of it over the G4 Hummer.

I like your feedback so far what type of riding do you do? You think these bikes are capable of small jumps and stuff?

Also pics would be great

Cheers
Matty

 

[dropbear]

kx 250

Hi guys just to let you know did 2 hrs today new plugs ok but have ordered good one $20 I will add a few pictures I'm intrested in learning more about the bike need heaver rear shock I'm 5'7 and 110kg so I need to cut the rear shock down about 35mm make it a biy easier to touch the ground.

 

[rowtree]

Hey fellas, im new here and havent ridden in quite some time. I have been contemplating picking up one of these Chinas (probably a Kuda) and have pretty much read this whole thread and would just like to say thanks to Rod, Doc, Weegee etc. your information and advice has been invaluable. Just by reading this thread has swayed me from maybe buying one to definitely buying one. Thanks once again and hope to join the club soon

 

[mattdriver]

Hi,
What level of expertise, (for maintaining and riding) would be required for this bike
Thanks, Matt

 

[rowtree]

I was just browsing the Atomik site and have found that the Atomik Fury is watercooled with the Zongshen engine. Just wondering if its the same as whats in the Hummer, just watercooled. I also noticed that the Atomik Blitz has a Loncin engine claiming to pump out 14kw. Does anyone know much about this engine?

 

[rodbox5]

Hey fellas, im new here and havent ridden in quite some time. I have been contemplating picking up one of these Chinas (probably a Kuda) and have pretty much read this whole thread and would just like to say thanks to Rod, Doc, Weegee etc. your information and advice has been invaluable. Just by reading this thread has swayed me from maybe buying one to definitely buying one. Thanks once again and hope to join the club soon

No worries mate - the more riders the better - and the more the Chinese will spend on development and making spares available.

The Hummer G4 - (or Kuda Pro if you prefer dealing with Atomik) is probably one of the best Chinese 250cc on the e-bay market.

I've looked a a few of the others - (and indeed just bought a 250cc Link for the wife) - but none have come up to the component and build quality of the Hummer. Maybe this will change (that's what competition is all about) - but for the time being, we're all pretty happy with the what we bought.

The Aussie dealers could support the bike a little better with spares - and could also be a little more QA orientated before they ship you the product - but that's the fast mail order market these days.

We've all said that the first company to get up and really support these bikes with spares and decent manuals will make a killing - and I still think that's right.

Welcome!

 

[rodbox5]

Hi,
What level of expertise, (for maintaining and riding) would be required for this bike
Thanks, Matt

Mate it's a full size trail bike with a seat height of 95cms - so it's perhaps not for the newby. Having said that - once you can handle it's physical size - it's a forgiving and easy bike to ride.

You need a few practical mechanical skills to own one - since you need to be able to set the bike up properly when first received - and then keep on top of maintenence as an owner - but this is pretty much the same for any bike.

 

[rodbox5]

I was just browsing the Atomik site and have found that the Atomik Fury is watercooled with the Zongshen engine. Just wondering if its the same as whats in the Hummer, just watercooled. I also noticed that the Atomik Blitz has a Loncin engine claiming to pump out 14kw. Does anyone know much about this engine?

Hi Rowtree,

Some folks are claiming these engines aren't the genuine article - but I can't comment, since I've not seen one.

Personally, I don't like the idea of a water cooled Chinese 250 - it's just another thing that can get punctured or go wrong.

The Zongshen air cooled OHC engine outputs a good 13.5 Kw's anyway - so what's the difference?

 

[Ingleburn]

The way you guys talk about them only makes me want 1 more but moneys pretty tight at the moment so looks like ill be dreaming for a bit longer. Besides the look on my boy's faces as they ride there bikes is priceless. Money cant buy that so for now im happy that i could get them theres.

 

[rodbox5]

For those that were following the saga of the 250cc Link - I've started a new thread to cover it (Cob & Co 250cc Link). That should leave this thread free to stay on subject.

 

[mattdriver]

I've been following this thread for a while now and have found it to be an invaluable tool and ( i think ) this would be the best guide for hummer owners or even potential owners like me deciding which bike to get. Thanks!
I went onto ebay today and noticed the hummer kx, i know this bike has been mentioned before in this thread, but how does it compare to the g4, or even the kuda &kuda pro. Thanks Matt

 

[dropbear]

hi matty02 I've only just run in the bike hav'nt taken it over any big jumps yet taken along the dunes and about 800m of whoops it was ok but bottomed out so I need to up the rear spring but same jumps would probably be ok ,near where I live we have about 60m on the side of the road through trees grader cutouts council dumps very technical not alot of speed but make you think and your nacked after about two hours Can ride the hole track in a day around 115km. Taking a risk but with no rego

 

[rodbox5]

I've been following this thread for a while now and have found it to be an invaluable tool and ( i think ) this would be the best guide for hummer owners or even potential owners like me deciding which bike to get. Thanks!
I went onto ebay today and noticed the hummer kx, i know this bike has been mentioned before in this thread, but how does it compare to the g4, or even the kuda &kuda pro. Thanks Matt

Matt - it's pretty much the same bike - which has just been given a different look. When the KX first came out, the factory used it to get rid of the old model Hummer's parts. The early models had the previous style welded swingarms instead of the new seamless billet types and a few other retro bits and pieces. Now the old components have been used up and the parts are pretty much identical between the two bikes - just the plastics and the muffler are different as far as I can tell. It should be an excellent bike.

 

[bananasboy91]

hey guys i need abita help with mine the chain is lose and i dont know how to tighting it can any1 help plz??
thanks

 

[rodbox5]

hey guys i need abita help with mine the chain is lose and i dont know how to tighting it can any1 help plz??
thanks

Hi Bananasboy,

Expect your chain to loosen a little as the bike is ridden.

To tighten it:

1. Loosen the rear axle nut

2. At the rear of each swing arm close to the axle nut, find the wheel adjusters.

3. Depending upon which model Hummer you have, the wheel adjusters will either be a screw and locknut type - or a rotating toothed cam.

4 If you have a screw and locknut type - first loosen the locknut then start to undo the screw a little at a time. As you undo the screw, it forces the wheel backwards in the axle slot - thus tightening the chain. Make sure you undo the adjusting screw on each swing arm the same amount - so as to keep the wheel and axle evenly aligned.

4a - If you have the rotating toothed cam type - just rotate the cam to force the wheel backwards and thus tighten the chain. Opposite the cam's teeth you will see a metal pointer, which acts both as a reference mark and a tooth lock. This makes it easy to ensure that both wheel adjusting cams are set the same, since all you have to do is count the number of teeth to the pointer.

5. When the wheel and chain tension are set correctly (20mm - 25mm of free play), you can then re-tighten the axle nut. Note that the axle nut needs to be tightened to around 60 to 70Nm on the torque wrench - which is pretty tight. This level of torque can actally force the wheel back further in the slot than the adjusters are set - causing the chain to be too tight.

6. To stop this happening, fold a rag and jam it between the chain and the rear sprocket, by rolling the bike backards. This forces the wheel forwards onto the adjusters - thus ensuring the wheel remains in the correct position whilst the axle nut is re-tightened.

7. Roll the bike forwards to remove the rag - your chain tension should now be correct. If you lift the bottom of the chain with your finger (somewhere around the middle) you should ideally get about 20mm - 25mm of free play. Note that it is better to have your chain a little loose rather than too tight. A chain that is too tight will damage both itself and your sprockets in a real hurry.

Since you are asking this question, I'm assuming you haven't replaced your Chinese chain with a good quality alternative. If this is the case - I would strongly advise you to get a DID 428 NZ replacement chain ASAP. The Chinese chains don't last long - and a breaking chain at speed can be catastrophic and really scary.

Hope this makes the procedure clear.