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The first thing I would do after a low compression test is check the valve clearance.

If its a 2 cycle, a burnt piston/ring. 4 cycle may have brunt valves/piston/rings.

AnswerI agree with above but would like to add head gasket or loose spark plug could be a contender as well but less likely then rings or valves, first ensure spark plug is installed correctly and if it is then remove exhaust headers and slowly crank motor past TDC a few times listening for hissing sounds, if not exhaust repeat with the inlet manifold if still not the problem then if capable remove head and check for noticable wear/damage on the sleeve, head gasket(usually diagnosed by looking for carbon deposits starting from the bore shooting out towards the outside of motor) and piston top and also check the piston ring/sleeve gap. imo if you get the head off and you can afford it replace the rings while your there ;)
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โˆ™ 2011-11-13 02:12:15
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Q: Why do you have no compression when trying to start your bike?
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Related questions

What causes no compression in a 2 stroke dirt bike?

No compression could be various things from your piston to your crank start with your piston by doing a compression test

Why wont your quad bike start?

The engine needs fuel, compression and spark to run. You are missing one of those.

My 80cc bike motor takes 30 min of trying to start it to start. how can i start it first try?

it shouldn't take 30 minutes, it sounds like there might be another problem with the bike

What is the compression of Honda XRM 125?

The compression ratio for this bike is 9.3:1.

Why won't a 2 stroke dirt bike start?

Mixture, compression, and ignition... at least one of those things is lacking.

250 yzf WHY IS IT hard to kick start?

If it is new because the bike has full compression if it is old its good because it still has good comperssion

How can you tell when your dirt bike needs oil?

your dirt wont start because if there is no oil there is no oil compression which will cause your dirt bike to not start Answer Before it gets to that point, perform regular maintenance and oil changes. This will increase the life of your engine.

Why is my 98 Ford V6 trying to start but wont and getting plenty of fuel?

It needs fuel, compression and spark to start and run. You're missing one of those.

If one cylinder head has no compression but the other on does the car should still be able to start?

It might sputter and sound like it is trying.

When does dirt bike racing start?

when does dirt bike racing start

Why wont my Brand new 49cc dirt bike will not start?

well there are two simple rules about anything motorized. have to have fire. #2... you have to have fuel. There is also a third rule need compression , but you probally have compression since its brand new

Trying to get title for bike that was in bankrupsy bike was wrecked you rebuilt bike how do you get title even a salvage title?

A detailed answer would depend upon what state you're living in/want to title the bike in. You can get some basic information, to start, here: http:/

1996suzuki rm125 has fire gets gas.why wont it start?

Have you checked the compression? It's needs to get good compression to detonate. If not compression , then check the fuel mixture screw on the carb. It might be getting to much fuel, when trying to start it, or it might be to lean. just a tip, never use starting fluid on a 2 cycle, it will cause a lean out and sieze the motor up.

How do you start dirt bike?

First make sure the bike is in neutral and push kick start down on right side of the bike.

Why does gas mix with oil when trying to start?

This could be that your rings are bad or that it is saturating your cylinder walls and going by the rings can figure this out by getting compression test.

What are the signs of a blown top end on a two-stroke dirt bike?

you will have no compression

You have a 96 Honda cbr 600 f3 and you am have to start it on the 10 attempt it might start also you do use the choke is anything else you could do?

Check the compression. If it has low compression it will always be difficult to start. I have the same bike. It is a really good starter, comparatively to other older 'cycles I own. 1) Check the fuel level in the tank, and be sure to turn the fuel switch (left side of bike below tank and seat) to "On", or even "Reserve" 2) In stock tuning, my bike likes full choke for cold start, in any ambient temperature, it likes to warm up with the choke on, until it starts to sputter from the rich mixture. 3) I believe this bike has vacuume tube that goes to the fuel petcock, this shuts off fuel to carbs when bike is not running. Thus if the bike has not run in a while, or the carbs drained, it will take several start attempts to get the carb float bowls filled. 4) This bike is hard to start if the battery is old or marginally charged. 5) Also pull the spark plugs, if they are brown, or black, change them. 6) check the air cleaner, if it is too dirty it will essentially act like a choke

What is established through compression testing?

Compression testing is done on engines and it establishes whether the engine has good compression. Good compression is needed for the engine to start easily and run efficiently.

Why engine does not start?

Does it have: fuel, spark, compression?

Where could you buy a custom bmx bike?

go to a bike shop and start to build it there start with the frame its the most expensive

How can you tell what year your dirt bike is?

I have a ktm dirt bike trying to find out the year the number is ktm8701*45853*

Why does your car make a loud noise while trying to start?

Becuse of the motor the belt spins and its pumping sence its starting up its kinda like how a bike starts you have to make a sound on getting on and start pettaling.

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I normally wore a Bike jock without the cup, but sometimes my baseball compression shorts.

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coil on side of fly wheel broke of can refit but want to rewire bike from start to finish key start to cut of switch to coil whole bike but need to know lay out of wiring of bike and replace all wireing

How much compression should a 3hp Briggs have to run properly?

My daughters mini bike with a 3hp Briggs has 80psi compression and runs great. A motor I got "running" off eBay has 55psi compression, runs but has NO power. -Jason