Achtung Noobs! : Your New Pitbike and You... set up tips

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thump*140

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Been having a bit of a look around the forum after a bit of an absence... noticed it's lacking a basic "initial set-up " thread... a question that seems to get asked repeatedly.
there is a sticky thread on the subject, but it's got pages and pages to sift through before you find all the info you need...
so here's my crack at it..

Regardless of the bike you buy, whether it be a dodgy no name copy from Ebay, or a high-end race-prepped mini from a reputable "real" bike store, they need the same work done before you ride it. The quality of minis will always differ, depending on their origin or source.. And I hope to make a point with this... all the minis/chinas i have, with the exception of my 04 Thumpstar Hunge-Ten have been the cheapest thing i can find on ebay or the like. All of them have done a heap of hours. All of them have dragged my 90kg ass through the bush, or over a mx track. All of them are still kicking, and they're all first kick starters..
INITIAL SET-UP AND MAINTENANCE CAN MAKE A $300 EBAY SPECIAL OUTLAST A BIG DOLLAR FIDDY THAT SUFFERED POOR SET-UP AND MAINTENANCE!!!!!!

So here you go. Mum has just pulled your new mini out the back of the commodore, or Mr Postman has just delivered your new weapon courtesy of Ebay...
You can either put fuel in it, fire it up, thrash it, then spends hours on this forum bagging the ebay store and finding ways to fix your bike, or you can spend the time in the shed BEFORE you attempt to kill it, and like my minis, 5 years on, they're still going strong...

You will need:
• Enough different sized spanners, sockets and screwdrivers to disassemble the bike
• A tub of basic bearing grease
• A litre of engine oil. 10w40 non-synthetic will do. It's a Lifan, not a Ferrari engine..
• A tube of Loctite, or failing that, pinch some of mum's nailpolish.
• A can of WD-40
• Dot 3 Brake Fluid
• If you are over 18, a six pack of beer.
• If you are under 18, a monster or red bull or whatever the cool kids drink now.
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Some bikes will come assembled, others require a small amount of assembly. Your best bet is to leave it in pieces if it's unassembled, if it's "whole", start taking it apart.

Wheels, axles and Headstem/Steering bearings
• Put the bike on a stand, milk crate, dad's lap, anyway you can get both wheels off the ground
• remove front and rear wheels
• When removing the wheels, it pays to put the axle back through the wheel, with the spacers on there in the order they came off. This will help get the alignment right when you put wheels back on.
• remove Top Triple clamp and handle bars. Throttle, brake and clutch lever assemblies can stay bolted to the bars.
• Slide the forks/bottom triple clamp out of the head stem. You will see a bearing race top and bottom of the head stem. Grease the bejesus out of these bearings
• Re-attach forks and bottom triple clamps to head stem, then reattach top triple clamp to forks/headstem. tighten all bolts on the triple clamps, but DO NOT USE LOCTITE ON THESE. do them up til tight, then give them one last "nip".
• Re-attach handle bars.
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Rear Shock and Swingarm Bearings
• Rear shock pivot points: remove the seat, sidecovers and rear guard. This will allow you to access the shock.
• undo the top and bottom bolts on the shock, and remove the bolts. Grease them up as best you can, re-insert and reattach shock to swingarm. (leave frame bolt out for time being.)
• Undo and remove the main pivot bolt for the swingarm. (where the swingarm mounts to the frame). Pull the bolt out, grease thoroughly and reinsert. Do bolt up, and fix with loctite. (Do not overtighten bolt. check for free movement of swingarm up and down. Overtightening may cause "stiff" patches in your rear shock action.
When you are satisfied the swingarm pivot bolt is tightened properly, re-insert the bolt for the top of the shock, where it mounts to the frame.
• Grab both axles, and coat them lightly with grease. Replace both front and rear wheels, and tighten axles. Do not use loctite on axle nuts.
• Check both wheels rotate freely, then pump both front and rear brakes while turning the wheels, to reseat the brake pads.
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Brake Fluid – Bleed, Flush and Replace.
• I have found that the last couple of years, the brake fluid used on new bikes is shocking, and as thin as water. I've actually seen a caliper seize, and a brake line explode cause of this rubbish. REPLACE IT BEFORE YOU GET ANY HOURS ON THE BIKE TO BE SURE!!!
• Remove the caps/covers off the brake fluid reservoirs for both front and rear brakes. (best done one at a time however to prevent spills)
• Top reservoir with brake fluid, and pump brake lever until it goes tight.
• Place drip tray under brake calipers on wheels
• Pump lever until it goes tight again, and hold brakes "on"
• Undo brake bleed nipple on caliper. fluid will come out, and lever will go soft and pull into bars or rear pedal will go down. before releasing the lever, tighten bleed nipple back up.
• Repeat process until fluid coming out of bleed nipple matches that of the new stuff you've poured in. it's a good indication the lines and caliper have been flushed.
http://www.miniriders.com.au/mini-tutorials/14996-video-brake-bleeding-masterspoon.html
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Loctiting nuts and bolts.
• While the plastics are off, it's a good time to check all the bolts and nuts over the bike to make sure they are tight, and loctite them into place. Trust me, this job will save you headaches after you ride it to the end of the driveway for the first time.
• Things like engine mounts, exhaust brackets, oil cooler mounts, CDI mounts, basically anything you dont want to lose, loctite it, tighten it up.
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There are differing opinions on this, but i never loctite the following:
• Countershaft sprocket cover
• Clutch and brake lever perches/mounts
• Throttle housing
• Bolts where plastics mount to the fuel tank, or seat base.
The above items will either need adjusting, or need to come off easily from time to time, and loctite can make that either difficult, or impossible and do more harm than good.
Engine Oil:
• First up, check if there is actually oil in the crankcase using the dipstic. Got oil?
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• Ok, now you can start it for the first time. put maybe a litre of fuel in the tank.
• Turn the fuel tap to "reserve" if it has it, otherwise just to "on"
• Turn choke on
• Kick away (or button start) until it fires.
• Allow the engine to warm on it's own with the choke on. once it's warmed, turn the choke off and give it a couple of squirt on the throttle. If you really have to, ride it to the end of the driveway and back, then turn it off.
• Use some sort of catch tray, and undo the main sump bolt on the bottom of the engine. Drain all the crap oil it came with, and dispose of properly.
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• It may pay to lean the bike over, and attempt to drain as much residue oil as you can. reinsert the sump plug bolt.
• Using a measuring cup you stole from mum's kitchen, measure out the required amount. Most engines will have the oil capacity stamped on the cases. Dont use more oil than recommended. it will overfill the cases, and you will have blowback problems, among other things, and it makes a mess.
• Pour in the oil, reinsert the oil filler plug, and with the killswitch or key turned to "off", turn the motor over a few times by hand just to start circulating the new oil.
• Restart the bike, and listen for any rattles etc, allow it to warm up, and feel free to ride the thing for a few minutes. Allow the engine to cool for ten minutes, and repeat the process a couple of times.
• Once you've done this, the engine should be right to go for a bit of a decent run. Dont hold the thing wide open for the first tank of fuel.
• While there are many trains of thought in regards to running in a new engine, i have always gone pretty easy for the first tank of fuel, with the occasional full throttle blast just to make sure. I've never blown a new engine, and have always got a good life from motors i've had.
• Assuming your bike ran fine through all gears, and all throttle settings, you should be pretty right from here on. After burning through the first tank of fuel, change the oil again. it's cheap to do, and good insurance on keeping your engine running for more than a couple of rides.
• If you have had problems with the bike running at different throttle settings, time to get on the "tech talk" section on here, and start looking at jetting problems. Nine times out of ten, incorrect jetting is the cause of bikes not running as they should, and in most instances can be rectified by either adjusting the needle clip position, or going to a smaller main jet. Please note this is a guide only, based on my experience with Mini engines as they come from the factory.
 
Chain adjustment:
• Put the bike up on a stand with the rear wheel off the ground.
• Undo the axle nut and chain adjusters.
• Push the whole rear wheel forward.
• Wind the chain adjuster back until chain tension gives you about 40mm of slack.
• Make sure the chain adjusters are adjusted evenly on both sides of the swingarm.
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• Put a screw driver or spanner between the chain and rear sprocket. This will put tension on the whole set up, and allow you to tighten the rear axle nut with correct alignment.
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• Tighten rear axle bolt, take bike off the stand, and sit on the bike. If you need to, get someone else to check the tension of the chain WITH YOU SITTING ON IT. You should have about 20mm of slack/movement in the chain. If you have more than 20mm slack, loosen axle and move chain adjusters back to remove slack. If you have LESS than 20mm slack, loosen axle and move chain adjuster forwards to add slack.
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• Once you are satisfied you have the right chain adjustment, tighten rear axle. The simplest way to tell if you have got the rear axle torque right, is that if you spin the rear wheel with the wheel off the ground, it should rotate maybe one full revolution.. any more, rear axle isn’t tight enough, any less, it’s too tight…


Cable freeplay/Brake freeplay:
Freeplay is always a personal thing, but for safety sake, basic guidelines can be followed. Usually freeplay of about 2-5mm on cables, and maybe 10mm on rear brake pedals is a good starting point.
• Undo the locking ring on the cable adjuster on the clutch perch.
• Pull the clutch lever in a little bit until you feel some tension against the cable. Measure the gap between the stop on the clutch perch, and the edge of the clutch lever where it hits the stop. Adjust this in or out until you attain between 2-5mm of freeplay.
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• Front brake lever: Pull lever in lightly until you can feel the master cylinder piston start to move. Most new brake levers are slightly adjustable in this regard, via a small bolt and either locking ring or grub screw near where the lever pivots on the perch. Undo locking nut, and adjust screw until desired freeplay is attained.
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• Throttle: twist throttle lightly until you can feel the cable start to open the carby. Undo the locking nut on the cable adjuster, usually where the cable exits the throttle housing. Either screw in or out, the adjusting bolt for the cable until you have about 5mm of freeplay before the cable starts to lift the carby slide. Tighten the throttle adjuster locking ring.
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• Rear Brake pedal: Most pedals have an adjustable nut where the actuating rod enter the rear brake master cylinder. Measure the freeplay of the pedal by pushing it down until the pedal has some resistance on it. This indicates that the master cylinder piston is compressing the brakes. Undo the locking nut, and adjust either up or down the secondary nut on the adjustment bolt until you have about 10mm of freeplay. Retension the locking nut.
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Other points to consider:
 Tyre pressure – Pump tyres to between 14 and 18psi.
 Oil the chain. If you don’t have chain lube in a can, you can drizzle engine oil over the chain by leaning the bike over and spinning the wheel.
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this is a pretty good guide thump, I never stripped my bike down fully like you say but I did most of this stuff.
one this you left out is valve clearance, on my pitpro 140 and my bro's pitpro 125 after a couple rides the bikes lost compression and ran like crap until I adjust the clearances then they were like new again. When I got my new lifan 140 a couple weeks ago The first thing I did was check the clearances, they at .001 inlet and .004 exhaust. So i think they should be adjusted before the and after the first ride and again after the run-in, then regularly after that
 
good to see a full list of pre first ride checks
no doubt some people would do some things differently

now maybe you could compile a list of maintenance checks after a ride, to help the noobs a bit more haha
________
PLYMOUTH CABANA SPECIFICATIONS
 
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All i have to say is wow. This is excellent ! Very good job when i first got my bike i did the once over of bolts and what not tyre pressure dropping oil blah blah blah i have only rode by bike 2-3 times and only once hard but throughout this week ill be doing this over the whole bike stripping the whole thing just like u have explained even have my thread lock sitting on the shelf waiting to be used ;)

Very helpfull and nodoubt ill be using this as a guide
Cheers Jason
 
Ha ha! This one was stickied before i finished uploading it all... Must be some sorta record..
*does cartwheel*

Thanks guys, hope this one helps a few people!
 
Very extensive reporting and for the most of it i applaude you, but there are some serious issues that may result in further damage so they need to be addressed: HOPE YOU DONT MIND!

1. Do not grease Wheel Axles, doing this will cause the wheel to rotate on the Axle instead of the bearings as intended. I would recommend greasing the bearings instead.
2. Do Not Grease Rear shock Mounts, most of the cheap chinas use rubber and grease will only make them deteriorate. Instead these rubber bushes should be replace with complete steel ones.
3. Same with the swing arm bushes.
4. NEVER, NEVER use the alignments marks located on a chinese bike swing arm as a guide to getting your rear wheel straight. These marks are never mirrored, instead...stand behind your bike line up the sprocket with the chain. (Running Straight)
5. Finding the correct chain tension on a china is very difficult, because in most case the Geometry in incorrect and the chain will either get tighter or lossen when the rider sits on it. If it gets looser, then throw the bike away. If it gets tighter, then allow 25-30mm slack with the riders weight on it.
6. No need to pyshically bleed front brakes, just pumping the lever by hand will result in bleeding air from the system as they are SELF BLEEDING.
7. NOT recommend bleeding rear brakes because once Air enters the system, most people wil not be able to bleed it out and will require specail bleeding technics by bleeding each part.
8. Running tyre pressures between 14-18 psi will infact allow the tyre spin on the rim causing the tube to tear from the valve. Use 25psi unless you have installed rim locks.
 
all round G-Sh1t right there, great write up. you dont relise some kids would actualy try doing work on there bike in a huge mess
 
Very extensive reporting and for the most of it i applaude you, but there are some serious issues that may result in further damage so they need to be addressed: HOPE YOU DONT MIND!

.

Not at all mate, all the help with these sorts of things is appreciated. With things like these write-ups, i'm happily corrected. :)
At the end of the day, we're all trying to educate those riders on here with less experience and know how than themselves.
i may have a lot of experience with bikes, but i do not profess to be THE authority on them, so anyone with ideas or corrections for some of these threads i'm doing, please, add what you see fit. :D
 
-thump 140-
i gotta hand it to ya mate your pumping out some nice decent threads! :D

im sure the rest will agree..
i will be following these tips when i move to minis.
 
chain tensioning; just what i was looking for. great piece, thump140
 
NRG thanks for that bit off extra info but im just wondering where i can buy them steel bushes
 
This thread is great! I am awaiting my bikes delivery and will follow these procedures
to maximise it's life !


Cheers
 
An awesome thread, thump put in alot of effort with his posts!!

This is a must read to all new bike owners as well as the slackers ; )
 

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