G'day from Queensland Australia

Xxxx

Welcome :D

Did you forget to mention the XXXX they make somewhere up there???
 
Hi,
I have a Kalahari with a 70cc Zbox motor. I've done 10,000 kms on it but the first motor disintegrated at 4000 kms. I've built 6 bikes now altogether mostly for friends. I think the single most important thing to do is to take out the engine mounting bolts that come with the kit and get replacements made from hard non-Chinese steel. It's nearly impossible to get non-Chinese steel bolt shafts but fabrication shops can usually provide US hard steel bolts if you search around. It doesn't cost much and saves a lot of trouble because the chinese bolts break and it's a real pain drilling out the bol;t shaft and having to helicoil the new ones in. After several breaks I found the above solution. Rear mounting bolts are the ones to snap first. Also the threads on the chain tensioner spindle strip within days - Chinese steel again. If you go to the Beijing games next year keep clear of the Main Stadium because that is Chinese steel too.
Drilling a hole in the front frame bar of the Kalahari to mount the engine hasn't caused me any problems after 10,000 kms - they have a very strong frame.
Cheers,
John from Brunswick Heads, NSW
 
Cool. Thanks for the welcome guys. John, I'm in awe that you've done 6000 kms on that current engine, let alone 10 000 on the Kalahari. I haven't relented on my minimal front mounting point, but your post makes me think otherwise. I launched it this evening and was impressed how it ran. Can't wait to see if it's fine come morning to really try and break something. lol. Cheers guys.

Cam
 
I should have been more clear

[I should have been more clear. The first motor, a 55cc chinese 2-stroke seized at 3780kms when it pulled one side of the gudgeon pin out of the piston and threw me over the handlebars. The second engine a 66cc chinese 2-stroke (sometimes wrongly called 70cc or even 80cc) started to make noises at 1300 kms and I replaced the rings and keep it as a spare. The thirds 66cc one was retired after 3400kms because I lost faith in it and didn'tr like the noises it made (I'll fix it one day). The fourth 66cc one seized at 2200 and became a garden onament. I could go on but it makes me ill with anger that the only problem with these motors is something I could easily fix in twent minutes if only had half a dozen Commandos and entry to the factory in China!
Irish john
 
I could go on but it makes me ill with anger that the only problem with these motors is something I could easily fix in twent minutes if only had half a dozen Commandos and entry to the factory in China!
Irish john

Heh. Commando Capitalism!
 
I live quite near you Cameron

I live in Ocean Shores and have a Kalahari with 70cc motor - my 4th motor on the bike. I can give you a few tips if you like but there is a picture of the bike on my ID thingy when I became a member. I'll try and attach it here.
I'm starting my own thread about my new 4-stroke project. Oh yes, put high rise handlebars on and even longer cables if you have to to make the gears & brakes reach but it will be so much more comfortable believe me. My bars are not high enough and need to be higher. Keep the saddle low and get a big fat sprung saddle - a Micargi one is $50Aus.
Irish John

Hi guys. My name is Cameron and I live in south east Queensland Australia in a place called Toowoomba, which is situated a top of the Great Dividing Range. So you can imagine there are some quite challenging mountain roads around.

I'm a 35 yo Aussie bloke and nearly everything I do is in metric, so bare with me if I blurt out something in mm. But since you guys have been sending quality machinery out here for all types of industry for the best part of the last century, I tend to swing either way.:-|

As you will see this is my 3rd post...oops. I was so eager to dive in and pick people's brains there was just no stopping me. This forum is just the ticket for us new guys to learn a thing or two and get some really helpful tips on building and safely riding these freedom machines.

Just took delivery of a 70cc Chinese frame motor this week for a 20" Merida Kalahari. Mounted most things on today, but I will say the rear sprocket tested me. Getting it true was a mission and my first launch will be a telling experience I'm sure. I've also gone a little experimental (perhaps prematurely) on the front mounting bracket, opting to use the water bottle cage mount. Which means I am basically tying the mount by just one 1/4" bolt. I've used rubber bushing where ever possible and it does feel firm. I'm not sure how much trouble I'd be in if the bolt sheered but I'll guess I'll find out this weekend. :)

Keep you posted.

Cheers Cameron H
 

Attachments

  • Motorised Bike1.jpg
    Motorised Bike1.jpg
    252.1 KB · Views: 116
Hi Blue Max

I found the best way to handle the front mount on a Kalahari is to drill a hole through the downtube that hold a long 8mm dia. bolt. Never use the bolts supplied from China cos they are like cheese. Use one of the rounded rear mounting brackets - there's thick ones and thin ones and the latter won't last - the dearer ZBox engine has the thicker brackets. Drill a hole for an 8mm dia hard steel bolt in the middle of the bracket and turn the bracket inwards towards the engine with the bolt head on the inner side. Bolt the bracket to the motor using 2 non-chinese hard steel bolts identical to the ones supplied. The long threaded bolt goes through the hole in the downtube and on the other side you put a big wide thick washer, a spring washer and a nylock nut. You have to put the front mounting in before you do the rear mount. The downtube is very high quality water formed alloy and will not break if you drill the hole to match the 6mm dia. bolt. I get my bolts from a bolt barn in Ballina and they are Aussie hard 12.9 steel (the strongest available) Bolts in most hardware stores like Mitre Ten are Chinese so watch out. The rear studs can be easitly made if you buy a hacksaw and an Aussie tap & dye set ($25Aus max) cos you'll need to make your own rear bolts occasionally. The 12.9 Aussie steel bolts can break too eventually but I've not had the front 8mm dia one snap - the 6mm dia studs have snapped twice in 10,000kms. The Chinese ones snap almost immediately with the 70cc motor's additional vibration. Throw away the Chinese galv steel exhaust strap but not until you've gone to a stainless steel fabricators and asked for a length of thick stainless steel strapping which they have lying about from off-cuts (usually costs nothing). Look at where the holes are in the Chinese one and drill similar holes in the stainless steel and it will make a lovely exhaust support strap. I use locktite in the rear studs but that is optional.
When the inevitable happens and a rear mount stud snaps take the motor off and get a good metal worker to drill into the broken bolt and try and twist it out without destroying the female thread. If the thread is destroyed you can retap it for an 8mm dia. bolt but that takes the hole perilously close to the edge of the casing. 8mm Aussie hard steel bolts have never snapped on me and the 6mm stud is a typical design flaw in the motor. Lastly, if you treat the motor nicely it will probably live a lot longer. I was forced to make my own studs because I install these motors frequently for people and can't bear to see them suffer the pain I endured before I learnt other ways. Now I'm off to start my own 4-stroke thread on MCc and I won't need my tap & dye to do it. Hope this is of some help Blue Max.
 
Back
Top