Going to try the new Hummer G4

[250cc4me]

I just purchased a G4 Tomahawk Hummer too - it should arrive sometime in the coming week

As soon as it arrives I'll get some photos up for those interested. If all goes right, my riding gear should also arrive this coming week so next weekend I can go for a ride on my new dirtbike

 

[rodbox5]

Hi Fellas - suddenly everybody is buying a G4 Hummer! My review won't be ready for a few weeks yet, until the bike's run in. At that point I'll be able to really put the bike through it's paces.

In the meantime - here's a few tips for when your bike arrives:

1. Fitting the handlebars: The bars have two ridged rings scored into their surface, which makes the fitting more secure. This works so well, you can't adjust the angle even when the bolts are loosened. You have to actually pop them out of the retaining clamp and then rotate.

2. The assembly instructions warn you about not using the front brake lever until the brake pads have been fitted - but be aware there are no brake pads fitted to the back wheel either. Be sure to fit the rear wheel brake pads before depressing the rear brake lever - otherwise you will have to release some fluid to push the brake pistons back in.

3. When raising the rear of the bike to insert the frame linkage pin - be sure to grease the pin well before insertion. Note that the other 2 pins which have already been inserted are not pre-lubed either - so you should give them a decent grease whilst your at it.

4. I don't know what oil or hydraulic fluids the Chinese put in these bikes before shipping - and for that reason I replaced all fluids with locally available products. I like Castrol Active 4T 4-stroke oil and I like Castrol fork oil 5 for MX work.

5. Be careful with the battery. Shorting it out on the frame is not only a lively experience - it can also damage the CDI ignition. Connecting the plastic terminal covers before putting the battery into it's box is a good start.

6. The fuel switch is connected to the tank right behind the diagonal frame brace - which (if you have large hands) makes things a little difficult. On mine, the fuel line was not connected - and this was an additional job I had to do. Be careful with how you set up the fuel line - you don't want any sharp kinks or to put it near moving suspension components. Use a tie to secure if necessary.

7. Get yourself a torque wrench and check the tightness on everything.

8. Be careful when running in. Run for fairly short periods and don't go past 3/4 throttle for the first 500kms. These bikes run hot at first - but will run progressively cooler as the running-in period gets toward the end.

8. Change the oil at 300, 600 & 1000kms - at which point the bike should be run-in. The oil drain filter and oil screen filter are both located internally. You will be surprised at how much metal accumulates in these whilst you are running in the bike - but this is perfectly normal. Just make sure they are cleaned out during the oil changes - and at subsequent service intervals.

 

[rodbox5]

Full Review as promised

Dreamrider Tomahawk model G4 Hummer Review.

I recently purchased a Tomahawk G4 Hummer from Dreamrider Inc. via e-bay. This is the first motorcycle I have purchased in some years and I did not want to spend a lot of money on something that might turn out to be a passing fad.

Finally, the reasons I chose this bike over the many others available on e-bay were:

1. Reasonable price ($1,225)
2. Full size configuration 21” front, 18” back 970mm seat height
3. Advertised improvements to power, technology and manufacturing standards, over previous models.

Delivery of the bike occurred within 2 weeks of purchase. The bike was securely packaged in a steel cage, with the front forks firmly bolted to a stout securing plate. The front wheel, and handlebars, (together with a few other bits and pieces of bolt on gear) were supplied detached from the bike, in order to save shipping space. The rear suspension linkage pin was also removed, so as to collapse the rear of the bike into a smaller package.

Upon arrival, only two minor problems were encountered:
1. The handlebar bridge was missing a M8 flanged nut.
2. The battery acid cells (shipped separately to the battery housing) arrived with the centre cell ruptured. The acid had leaked out and had burned/stained the bottom of the shipping carton. Fortunately there was no damage to the bike – and $4.50 purchased 1 litre of replacement electrolyte, from Battery World.

A quick look at the assembly instructions and the owner’s manual confirmed my pre-purchase expectations – both were poorly translated, poorly illustrated and far from comprehensive. I think the owner’s manual was actually written for another model, since none of the technical specs seems to match my bike!

The bike on the other hand was a different matter altogether. The build, fit and finish of the bike was pretty good and I have to say, exceeded expectations (especially given the price)! For those who remember the older model Hummer, much of the welding in critical stress areas has been done away with – to be replaced by solid machined billet components. The general quality of the remaining weld joints is difficult to assess – since much of it is covered with paint/powder coating. However that said, the visible welding on my Hummer varies between very good - and slightly marginal here and there. This is not surprising considering how fast they must be putting these bikes together to achieve the price – bust most importantly, all the welding located in critical stress areas, looks pretty good.

In putting the bike together, it soon became obvious that additional details (not covered in the assembly instructions) had to be attended to. To make things easier for anybody purchasing one of these bikes – I have listed some tips below:

1. Fitting the handlebars: The bars have two knurled rings where they locate into the bridge mount, so as to make jointing more secure. This works so well, you can't rotate/adjust the bars - even when the bolts are loosened. You have to actually pop them out of the bridge’s retaining clamp, rotate the bars to the required angle and then press fit them back into the clamp. You then just re-tighten the bridge bolts and the job’s done.

2. The assembly instructions warn you about not using the front brake lever until the brake pads have been fitted – but be aware that the rear brake pads aren’t fitted either. Be sure to fit the rear wheel brake pads before depressing the foot brake lever - otherwise you will have to loosen the bleed screw (to release fluid pressure), whilst you push the brake pistons back into place.

3. When raising the rear of the bike to insert the frame linkage pin - be sure to grease the pin well before insertion. Note that the other 2 pins in the linkage system (already fitted) are not pre-lubed either - so you should give them a decent coating of grease whilst you’re at it. The best way to do this is to support the bike under the forward part of the sub frame – so as to let the back wheel hang free. You then shim the back wheel with a piece of timber, until the height is just right to slip the linkage pins in and out. This will save you a lot of heavy lifting – not to mention a strained back! If you can afford around $100, a mechanical bike lift for this kind of work is a good investment.

4. I don't know what quality of oil or hydraulic fluids the Chinese put in these bikes before shipping, so I replaced all fluids with locally available products. Castrol Active 4T (4-stroke oil) is cheap from Woolies and works just fine in these bikes. For brake fluid, I generally use Castrol or Ferrodo Dot 4 – which is again cost effective and works well.

5. Be very careful when installing the battery. Shorting out the terminals on the frame is not only a lively experience - it can also screw the CDI ignition. Securing the plastic terminal covers before inserting the battery into its box is essential. The battery is also a tight fit – and for that reason I trial fitted the unit before putting in the battery acid and making it live. In my opinion the battery terminals are on the wrong side of the battery. If they were the other way around, the battery could be installed with the terminals at the front, making the possibility of shorting out on the frame much less likely.

6. The fuel switch is connected to the tank right behind the diagonal frame brace - which (if you have large hands) makes turning the fuel on and off a little tricky. On my bike, the fuel line was not connected - and this was an additional job I had to do. Be careful with how you set up the fuel line - you don't want any sharp kinks or to put it near moving suspension or hot engine components. Use a tie to secure if necessary.
Continued in next thread...........

 

[rodbox5]

7. Get yourself a torque wrench and check the tightness on all critical fastenings. Some bolts have a dab of red paint to show they have been torqued to the specified value – but don’t trust them. I found very few fastenings that matched the torque specs in the manual. Almost none of the non-critical fasteners have been tightened past hand tight – so again, check everything with a spanner. On critical fastenings I applied some Lock-Tight – just to be sure.

8. Be careful when running the engine in. Run the bike for fairly short periods and don't go past 3/4 throttle for the first 500kms. These bikes run hot at first - but will run progressively cooler as the running-in period gets toward the end. The good thing was that after assembly and checking, the bike started without hesitation on the first go – always a good sign in my book!

9. Change the oil at 300, 600 & 1000kms - at which point the bike should be pretty much run-in. The oil drain filter and oil screen filter are both located internally. You will be surprised at how much metal accumulates in these whilst you are running in the bike - but this is perfectly normal. Just make sure they are cleaned out during the oil changes - and at subsequent service intervals. Running in the bike this way is a little tedious – and harks back to the days of the old British bikes, which were not run in on a test bed. Trust me though, the extra care taken running the bike in will pay dividends in both engine life and performance.

10. The manual doesn’t tell you how to set up the suspension, in spite of the fact that both the rear shock and front forks are pretty good units and fully adjustable.
Setting up the suspension to match the rider and conditions is essential to any bike and will considerably improve handling and performance if done correctly.
Essentially with the Hummer, you should set the free sag to about 30 – 35mm and race sag (with rider) to between 95 – 110mm. If you don’t know how to do this, there are many articles on the web that will show you how to tune your suspension properly – just Google it. The rear shock is also adjustable for compression and rebound and the front forks are adjustable for rebound only. You can however vary the compression characteristics on your front forks by using different viscosity fork oils. Again, there are many articles on the web which tell you how to do this and how to optimize the compression and rebound settings to suit your riding conditions. The spring in the rear shock is good for a person up to about 85kg’s in weight. Any heavier and the spring is struggling to perform at its best and you should really be looking at a replacement unit with a higher spring rate. Unfortunately Dreamrider doesn’t carry heavier springs as an after-market item, but if you’re willing to pay full Australian prices, they are available from the custom suspension boys – but please be prepared for a price shock!

11. The stock tires that come with the bike are fairly budget quality hard terrain units, which are not really suitable for the soft riding prevalent here in Perth. None-the-less I used the stock tires to run the bike in – and then changed over to a set of Motoz Tractionator X Circuits – really great tires!

12. Because Zongshen’s new OHC engine produces a few extra horses over the pushrod model, they have opted to provide a smaller rear sprocket (41 tooth) with this new model Hummer. I suspect this was so they could claim a high top speed of 140kph + in the brochure. The reality friends and neighbors, is that this bike will take a long time to reach that speed! I therefore opted to change the sprockets over to a 16 tooth drive and 56 tooth driven (rear) sprocket. This gives you a drive ratio of 3.5 - which is pretty torquey and provides heaps of acceleration and hill climbing ability. The theoretical top speed will of course suffer – but there aren’t many tracks around here where I can use 140 kph!
I’m also waiting on a 47 tooth sprocket from Dreamrider, which I will run with a 15 tooth drive sprocket, giving a drive ratio of 3.1. I’ll then have two drive options, which should cope with most places I ride. To allow for the larger sprocket, I ditched the original chain and opted for a DID 428 NZ black & gold. Note that this chain has a higher stress rating than the DID O-ring chain and in fact you’d have to spend big bucks and go to the DID premium X-ring chain, to get a higher stress rating. Rest assured, the DID 428 black & gold is a competitively priced chain and is just about ideal for Hummers!

13 In riding the bike, I found that it handles pretty well and with the 56 tooth sprocket and accelerates quickly on a short technical track. The suspension tends to bottom out on jumps and in the whoops – but that’s probably more to do with my 96kg weight than the bike. Inevitably I’m going to have to bite the bullet and look at a custom spring on the rear shock. None-the-less, for general work around the track, the bike behaves well and provides good cornering and agility. Note that much of this performance has to do with the choice of tyres and the suspension set up – so pay attention to these elements when setting your bike up!

14. One thing I don’t care for are the bike’s foot-pegs, which I think were designed for dainty sized Chinese feet. Personally, having size 13’s and MX boots, it feels like your standing on a pair of nails and some after-market oversize pegs would definitely be the go. Unfortunately most of the after-market boys don’t make oversize pegs for Chinas – mainly because three sets of their pegs would buy you a new bike! The only oversize peg made in Australia to fit this bike costs nearly $300, so I think I’ll wait for an enterprising Chinese company to catch onto the oversize foot-peg market, or maybe have a go at making some myself!

All in all the G4 Hummer from Dreamrider is a great bike for the money and provides an incremental step forward in the quality and manufacture of Chinese bikes.

I’ve been thinking that down the track I might look at some power improvement options – and there are a couple of books on the market which can tell you how this is achieved. Recently though, I discovered a Philippines based company on e-bay, which produces monster trick versions of the Zongshen 250cc engine for just U.S.$499. Power outputs are claimed to be up with the top Jap and European bikes – and a heavy duty custom clutch is included with the package. The only question I’d have is whether some custom sprockets would be necessary, so as to enable an upgrade to a 520 or 530 chain!

Anyway, for those who may be interested, The G4 Hummer is available from the following site:

eBay Shop - Dreamrider Store: Hummer 250: NEW 250CC TOMAHAWK G4 HUMMER pit dirt trail motor bike

The Tricked up SOHC Engine and other accessories are available from this site:
eBay Store - Zongshen performance: Performance parts, Appearance and beauty, Hausmotors

Enjoy the ride!!
Rodbox5

 

[CibbyDoc]

Rodbox5....i have one of these bikes and totally agree. Value for money no doubt about it....build quality is above expectations for sure.

Back up from dreamrider.....suspect. Quick reply's like you say but not much knowledge or support.

Does anyone know what the replacement spark plug is for instance?

Not much help from dreamrider with that one either and the original LG D8 dosnt even exist according to NGK.

First post so I dont mean to hijack your thread, but I bet there are lots of people now owning these China miracles and this sort of info would be a big help.

Regs CibbyDoc

 

[rodbox5]

In my manual the plug is specified as a Torch D8RTC - which is a Chinese made plug
Denso Plugs have a chinese cross reference table, which identifies the following two Denso plugs as being equivalent
X24EPR-U9 (Standard)
or
IX24B (Iridium)

Using the Denso numbers, NGK cross reference tables list the following NGK plugs as equivalent:
DPR8EA-9 (standard)
or
DPR8EIX-9 (Iridium)

Cross reference tables can be a bit "iffy" on occasions - but this is the best that can be done. Eyeball the original plug against the suggested replacements - and if the various dimensions look the same - it's usually O.K.

As a seperate matter of interest, I notice that Atomik are also marketing the new G4 Hummer under the model name of "KUDA" - so there's another possible source of information and parts. The problem I've had with Atomik is getting them to answer your e-mails in the first place!

I'm also offering to re-write the owners manual for Dreamrider - which will keep me offline here for a while.

If just one of these companies would stand up and support their bike with parts, good manuals and a help desk - you think they'd clean up. All they seem to care about though, is getting as many units of stock out the door as possible!

I'm sure the Chinese manufacturers would also welcome product field reports and customer feed-back - but I doubt the resellers provide that either.

I'm sure the China bike makers have no idea what abuse the kids in the West put their through - I bet they'd be shocked into beefing up the build here and there - Ha Ha

 

[CibbyDoc]

News Just Inn.................Ngk replied to my email and have sourced the appropriate plug for the ZS167FMM SOHV engine...its the NGK Spark Plug Model - DR8EA.

Onya NGK.......

You're right mate...spoke to Ben from Dreamrider about this exact matter. I've spent some time in China (Nanchang) where a lot of these components are made. They thrive on feedback and believe it or not most do have a type of R&D section...not what you might think, but its there.

Ford USA have now opened a plant up and are making Ambulances, commercial and Industrial/plant equipment.

If these guy's got info on the use and any major issues...they would correct them. Thats a fact!

Thanks for the info on the plug....my manual must be different to yours still again. Mine is listed as an LG/LD D8....thats it!

Have you had anything to do with the head and or tappets yet....mine seems a bit noisy at the mo and will have a look at it when time permits. Dont know if its shims or adjustable and I suspect the "AIRVALVES" referred to in the manual are the clearances...but not sure as the manual is for a 150/200cc. I guess the only difference would be bore and stroke.

Overall I have been extremely happy with this bike. I have owned a lot of dirt bikes in the past, last one being a XT600L Yam and I am pretty impressed with its capabilities.

Your right about the suspension. I have "DUCKS" disease (arse to close to the ground) and have dropped the forks in the triples by an inch and softened the rear end as well. I'm 78kg's and its fine for me but suspect it will soften in time...have also had to scallop the seat for me as well........yeah I can hear the short jokes now.

Ben from Dreamrider did say however that they will be offering a 19" - 18"
wheel version from about mid December 2007, which will help the vertically challenged like me.

Will keep an eye on your thread with interest and share any info I get.

Regs CibbyDoc

 

[rodbox5]

It depends on where you are in the running in process as to whether you need to worry about tappets.

The hummer is a bit noisy in this department during the run-in - however as I said in a previous thread, it's a mechanic's bike that needs adjusting now and then.

If you're still running in - then expect a little noise. If you've already run the bike in - then maybe it's time to check the gaps.

It's not a bad idea to check tolerances on a regular basis anyway - develops good habits and helps you get to know the bike.

 

[CibbyDoc]

Well the one thing it has done for me is make me angry. Am about to fire off an email to Dreamrider asking them to "PLEASE EXPLAIN".

I have taken the tappet cover off only to find....PUSHRODS......yes thats right.

The advertised 12.5kw of power from the new Zongshen overhaed cam engine has somehow changed to being a pushrod engine overnight.

Not happy Jan.

 

[rodbox5]

Hey Cibby,

I've only just finished running mine in - so haven't had a look at the head yet.

I'm off to India for a week on a business trip - but guess what I'll be doing when I get Back?

Things may no be what they seem however. I remember when buying the new Hummer, that one of the e-bay feedbacks said the bike wasn't a true OHC - but then the comment had been withdrawn by mutual agreement.

Also, the guys in the Phillipines (who do the hot version of the Zongshen OHC engine), mentioned push rods in their improved components list. I thought it was an oversight at the time and that some text had been mistakenly carried accross from ad they do for the hot pushrod engine. Now however, your observations would cause me think again.

At the end of the day though, Dreamrider didn't say the engine had no pushrods - just that it had an overhead cam. You may find that the operating cam is indeed located overhead - but operates pushrods using some weird ass transfer mechanism.

Anyway, let me know what Dreamrider says on the matter. If there's no clear answer by the time I get back - I'll take mine apart and figure out what's going on.

 

[CibbyDoc]

Will do Rod...nothing back as yet. From what I can tell by Zongshen's Intl website they do make a true OHC 250cc, but will see what Ben at dreamrider has to say, before I push the point...have a good trip. Cheers Doc

 

[Franky]

New McDonalds Crispy chicken burgers.
The all new sleek design and overal appeal of the burger is a good upgrade
from the McChicken. Being only that the McChicken only has to offer Lettace, Sauce and the chicken fillet deep rfried, not only was the crispyness not of saticefactory appeal, but the Cripsy McChicken could have not come at a better time, It has to offer from the standard, through to the delux, Standard only having the new crispy fillet, sauce and new style bun, And the delux offering the works, etc tomato, lettice, sauces, crispy fillet also on the new designed bun,

I rate the burger 0/10, Cause it tastes like ass,

 

[$heepy]

hahaha i laughed

 

[CibbyDoc]

Thanks for that insight franky....very interesting. Its pleasant to see your intelect is matched only by your taste for ASS or perhaps ARSE...as we who can remember how to write in english call it...good luck with your donkey eating anyway.

 

[CibbyDoc]

Still not heard from dreamrider after 4 days.

The OHC motor does exist and is available...so still not sure whats going on.

 

[rodbox5]

Hi Cibby - got back on Sunday.

I checked with the guys in the Phillipines, who make up the high performance version of the Zongshen 250cc OHC engine. Their's are the standard OHV arrangement, with a chain run cam operating the valve mechanism directly.

It's a gorilla of an engine with ceramic coated piston, high volume custom ports, high compression head, 3 option cam kit, stainless valves, teftlon seating and beefed up clutch - all for Aus$499

Sounds like D/R have an interesting question to answer!

Now I'll have to find out if one of the above engines will drop right in my bike - or whether we've got some none-compatible interim model!

I'll be bloody annoyed if we have!

 

[rodbox5]

Atomic are also now selling this bike under the name of the "Kuda" - they also claim it to be a 12.5kw OHC engine

If you get no answer from Dreamrider - you could always ask Atomik

 

[Weegee]

I have one of the atomic Kuda bikes and mine seems to be a great bike great fun to ride, but I have sneaking suspicion the it is a push rod engine too!
Can you supply any other photos of your engine because I want to see if the looks the same as mine, from what I can find on the net the OHC zonshen 250cc engine has a round part on the rocker cover (opposite side to spare plug) and mine defiantly does not but all in all I only paid $955.00 of eBay for it so I am not going to start complaining now as I see it I am still nearly $8000 in front of a new jap bike.

 

[rodbox5]

Mine appears to be the same.
It's strange though - we put the bike on a Dino - and it output the claimed 12.5 kw - just over in fact.
So it's not the old P/R engine - which only logs up 11.5kw.
As you say, the bike is great to ride - and with the 56T back and 16T front sprockets - is pretty lively
We'll just have to see if Cibby gets an answer from Dreamrider

 

[Weegee]

Ok i have just read the advertisment thoroughly regarding my Kuda Pro Hummer (atomic) and it does not state ohc like i thought, it only mentions the new evo 2 hummer engine, so as you say it must have more grunt than the older push rod engine.
But all i know it that i weigh 102Kg and it pops up the front wheel just by opening the throttle in first gear so not so bad, i think thats enough just for ploding along on trails and having a good squirt every now and then for me anyway.