125cc 4stroke Bike - First Timer Questions! oil. fuel. etc.

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macka

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hey guys,

As mentioned in the new introductions section, i have just purchased a 125cc 4stroke manual bike, and i have a few questions regarding it.

I have not received it yet - i know i could wait till i get it, but i want to sus out my options before it arrives to keep me busy!!

1. What oil do you recommend to use, and how much is it ? I dont want to spend outrageous amounts on oil if i can get something cheaper which does the job and performs fine.

2. What fuel do you use on your bikes ? i have heard that Ampol/Caltex Vortex Premium is the best one to use ?

3. When the bike arrives, should it have oil already in it ? or does transport regulations prevent that from happening ?

4. Whats the best way to wear the bike in ? Take it easy on the throttle and gears until it has had a few kms on it, or take the bike through all the gears with relatively high revs etc to break it in?

Thankyou in anticipation for your help!

..::MaCkA::..
 
Ok heres my opinion

1. For years I have used either castrol 4t motorcycle oil (NON synthethic) or Valvoline xld premium which costs around $16.00 for 5lts. I have used both on everything from xr600s to xr50s and never had a problem. Just make sure you keep your oil clean.

2. Most of these engines run perfectly well on normal ULP, but running vortex etc if you want is ok. If you mod your engine (raise compression etc) then premium is a must.

3. Change the oil before you use it as you don't what they have put in it! :lol:

4.The 2 big don'ts with running in is continuous high revs or lugging in to high a gear. Short bursts to highish revs wont do any harm. What I have done with good results is to accelerate at large throttle openings but not allowing the engine to reach full revs. This loads the engine allowing the rings etc to bed in better than if you baby it. Once you have run around 4-5 tanks through it you can pretty well ride as you like. Just remember to change the oil often during this time.

Hope this helps, it is only my opinion but it works for me.

What did you buy?
 
1. What oil do you recommend to use, and how much is it ? I dont want to spend outrageous amounts on oil if i can get something cheaper which does the job and performs fine.
i use motul as i told u in msn i stand by it 100% for gearbox,premix,oil injection i am testing motorex in my husky

What fuel do you use on your bikes ? i have heard that Ampol/Caltex Vortex Premium is the best one to use ?
use normal unleaded for the first 5 tanks in four strokes 5 tanks will last u yonks

When the bike arrives, should it have oil already in it ? or does transport regulations prevent that from happening ?
you bought the bike we bought so change the oil after every 5-8 hours use as the clutch plates/friction plates are shit they are like the kawasaki it leaves all little specs of metal in the oil and u dont want this floating around in your gearbox

Whats the best way to wear the bike in ? Take it easy on the throttle and gears until it has had a few kms on it, or take the bike through all the gears with relatively high revs etc to break it in?
go up to 3/4 throttle or u wont be happy on these bikes the beefy end is at the end of the rev under 1/2 throttle its a slug :p do not try to fang the bike quickly slowly but steadily rev and change gears etc... you need to understand these bikes need to be ran in if u thrash the bike from the get go u can bend the valve rods causing the piston to hit the valves smashing it and all sorts of problems if u look after the bike it will look after you!
 
Use a good oil you can afford to replace regularly. Any new reasonable quality oil is better then any oil thats done a feww hundred kilometers. So unless your buying Mobile 1 for $60 just get a good midrange like penrite, caltex, havoline specifically made for four stroke motor cycle engines.

Definitely replace the garbage oil that comes in it.

You definitely do not need to run premium ULP, nrmal ULP is fine it will have a 92 -95 octane, shell is the only one with 95. To go higher is no advantage unless you run higher compression. These things only run at about 9:1 so just run ULP. Only bikes with 12:1 and higher compression benefit from Premium.
Vortex is nice and clean.

The two critical things with break in is you must avoid a siezure by avoiding peak temps. So run it for shorter periods, with good air flow and when it smells hot stop. The second critical thing is that the ring/ rings become heat treated to a certain shape with the first ride. Thus the first ride must start the bike warm it on idle for a min then put the bike under load (not high high revs), but moderate say 3/4 revs for a minute or so on and off. Then shut the engine off so the ring matches the bore.

If you just idle it round the first time and cool it the ring doesnt have enough pressure to force it out against the bore and thus it is heat treated and sets as a poor fit to the bore. Causes blow by sooner and loss of compression sooner.

So the first run is the most critical. The rest are just a matter of avoiding peak revs and not letting it get too hot.

Remember this baby has valves so the two most important things you can do for it is a clean oiled air filter and fresh oil.
 
forgot to add u will need to clean or replace the oil filter (located left hand side of motor behind the crome cover with zongshen on it)when u change the oil also u will need to check the bike every time u ride it check the rear shocky make sure its strait im sure yours will be bent aswell :evil: check the foot pegs these will probably bend (slightly) after the first ride or two make sure the clutch is adjusted properly do this before u ride u dont want to burn out the clutch first ride ours was set way off and check for fuel leaks and replace the shitty fuel filter and one last thing your stearing might be a little stiff have fun and good lucky :lol:
everyone likes different handle bars but the stock ones are crap i got arm pump within 10mins of riding :(
 
just a quick one if u havent payed for the bike yet ask him if u can buy one of the bikes from the new stock it could be better than the one we have :evil: and it has trick looking disc's
 
hey guys,

thanks for all your help!

Gazza - i believe this bike is from the new stock as they said that they will start shipping mid to late next week as the new shipment is coming in on wednesday. Should have it by next friday or at least the following monday august 1 at the latest!

i hope i dont have as many problems as you have - i understand that most of these bikes are obviously cheap builds and regular maintenance is a must, but i guess thats like anything.

I'll take all of your advice and replace the oil upon receiving it, and i'll make sure that i run the bike in correctly.

Cheers for all of your help! any more advice can't hurt either!

..::MaCkA::..
 
hey there,

the link for my bike is here:
http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&rd=1&item=4562920610&ssPageName=STRK:MEWN:IT

i know it looks the same as yours but i emailed them the other day and asked about the bike/brakes and they said:

"Hi,

The brakes are a different shape but same calipers on the next shipment in the new auctions"

I know a few of you on these forums have had problems with these bikes, but i have emailed about 10 people who have bought the same bikes from woelfe_sport in the past few months and they claim that they have had no issues at all with the bike and they have been jumping, thrashing etc etc it, so hopefully i dont get the bad stroke of luck which some of you guys have had.

Anyway, it shall be arriving either friday or monday so i will let you know how it all goes!

cheers,

..::MaCkA::..
 
i cant say that all of those bikes will be faulty but i can say the people u emailed on ebay wouldnt have the best of knowledge on motor cycles some even gave good feedback without testing the bike with our bike the rear shocky was not a 1 off they will all bend to some point the chinese made way to much clearance
just a few pic's to look at this rear shocky would look fine to most people that dont have the slightest knowledge....
PICT0152.jpg

PICT0153.jpg

PICT0156.jpg
 
fair call on that, however i specifically emailed people that won the bikes at least 1 month ago so that i knew that they would have had a fair amount of use on the bikes since that time.

you told me that all this damage on your bike happened after 3 hours of use, so if these people havent had any known issues and they're still jumping, thrashing etc etc them at least a month later, im thinking that maybe you were just an unlucky bad case.

i have no doubts that there's going to be constant maintenance on the bike, $850 cant really assure that everything is going to be 100% perfect. i'm willing to run that risk, but yeah.

thanks for your words of warning and help regardless!!

..::MaCkA::..
 
no probs mate, ive only seen 2 bad bikes and heard of another 2 i hope yours turns out good my gf wont even ride her bike now shes scared it'll break more :x
 
Have to agree, I can't see that any of those shocks are going to last long, my 10 yr old bent it in no time and he wasn't riding hard. I finished modifying the rear end and fitted an Ishock, you wouldn't believe the improvement! More travel and better over jumps etc. This is one thing I won't have any more trouble with. I'd post some photos if I can work out how :? . My kickstart lever is just starting to bend :cry: have to find something stronger, I strengthened the foot pegs after one side bent far enough to jam the rear brake on :shock: . This happened with my 10yr old doing some small jumps! I fitted an unifilter as the original one started to show signs of letting in dust, made a chain roller, replaced the rubber chain slipper with a nylon one and repositioned the muffler so that the tire doesn't hit it. All this took more time than money, but should you have to do it to a new bike? I know we didn't pay a lot but the bikes do have some basic faults that they shouldn't have regardless of price. It's a shame because they could be really good little bikes if these faults never happened.
A bit of customer service wouldn't hurt.
Three phone calls and 10 emails and I am still waiting for my new tank..... :evil: .
 
eatslikehomer, any signs of the gear selector bending down? sounds like your having just a hard time as me the dealer wont replace your parts they are a.. h.... i wont buy from him again and we need to chase up some replacement parts to sell the bike argggg
something i noticed the dealer was knocking the cheaper motors over the zongshen but now he is selling the cheaper motors wtf????
 
gazza, I don't think he cares what he sells, cheaper motor = more profit. He's sold who knows how many bikes and I'll bet that most will have at least some if not all of the problems that we have had before long. All of the problems are either design faults or poor materials and I don't think for a minute that ours will be the only ones. Gear selector ok at the moment, the bike had a few good runs over the weekend and things seem to be ok for now. Are your going to keep yours or flog it off?
 
the bike i seen on display was shocking :shock: we are getting rid of our bike not worth keeping we need a reliable bike as im getting my missus to start riding in the bush wolfe sport had atlease 100 of these bikes that i seen in there ware house i feel sorry for all the others who bought it
does your son get arm pump from the handle bars? my arms cane after 10mins riding
 
my arms cane after 10mins riding

Can you explaine cane?

I produce bikes in china and on our new model (it owns all thumpstars big time) we were thinking of putting slightly longer handlebars as a customer has made a request.
 
Bromley what are you doing digging up old posts that have no meaning anymore?

It seems like all you want to do is put a plug in for your products wherever you can go....
 
damn thats one bad review! it's a pity they don't look to bad when they put on their nice showroom photo's up on ebay.
It would make a good bike for all the bench racers.
 

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