20 Most Recent 2008 Honda CRF 150 F Questions & Answers

DO NOT BUY A NEW CARB.. they RARELY "go bad".. you need to find a TRULY QUALIFIED PROFESSIONAL to work on this bike,,, find someone that has been to HONDA SCHOOL in the last 10 years...

Oil breather into Airbox is Blocked maybe?? That would 'pressurize' the block. Check ALL Vents/Hoses/Valves (some release valves are one-way ONLY). Good Luck with it. For more Bike stuff, goto YouTube/CrashTestDummyTV. Cheers >:)

.003 for the intake and .005 for the exhaust should do nicely.

Hi this is not a permenant fix but before you take it for a emission test you wana make sure the engine is red hot ,clean oil,clean fuel these are the only things that could cause problems with a carbon test im not over familiar wiv the 150 but i assume there is no computer as these can sometimes make sensors tell lies if so then i would suggest looking at this aswell.Hope i have been of some help

Have no idea what the bike is except its a HONDA so hard to give accurate answers! in most newer bike the cam chains would be auto tensioned so depending on what your bike is possibly could tighten it manually but unlikely
if the bike is old ?? then the cam chain can become over stretched and still slap about no matter how it is tensioned
also likely knock cause would be piston slap which occurs when the piston and cylinder gets bit old in the tooth
I would need to know age of the bike but more importantly what model of the bike as us mechanics at least need to know if has 1 cylinder or 4 cylinders to help you guys

You need a 16mm (5/8") socket.

its the flat head screw that is actually inset in the carburetor, and it should be a brass screw

The drive chain for the rear wheel does not get timed. The chain for the Over Head Cam ( OHC ), also does not get timed. In both cases the position of the chain doesn't matter. What I think you are asking is how do you time the OHC? There will be a mark, or marks, on the cam gear(s). The gear (attached to the OHC ), is what gets timed. Put the piston on TDC then refer to the diagram below.

Check your compression I will bet very low. Time for a top end rebuild

Helminc.com sells original Honda manuals on line.

To know if it is too rich or too lean or if its ok , you will have to remove the spark plug i.e. after a short run.
If the spark plug is blackish sooty thn its rich, if its totally whitish thn its lean, if is brownish, its ok.

To adjust this you will need to set the air-mixture screw. Tighten it all the way in slowly taking care not to overt tighten it as you may damage the tip of the screw, thn unscrew it 2 &h alf to 3 turns outwards, start your bike's engine and monitor, you may thn go either way alittle to suit the idling.
Best would be to replace the saprk plug.
Hope this helps!

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You have a vacumm leak.

Hello, Ebay would be a good place to look for them! Can get them Way cheaper there! Here is the trick to getting stuck grips off a bike without ruining them! Use Compressed air to remove them. Take the hose of air compressor 125PSI with a Blow gun attached to it. Now on the Flanged part of the grip put the blower end between the grip and bar and hit it with air. If it does not fly off gently twist the grip and it will most likely come right off! Here is another trick! Put them on in the reverse manner! To keep them in place I use Hair Spray Like Finalnet. It makes the grips go on easy and when it dries it will hold the grip on like Glue! Have a Good one!!
Remember Road Rash Hurts! So keep your Chin up!! Rick

Lift the corners on the back side.There is a bolt on each side underneath the seat material.

Google " motorcycle salvage Honda " You should be able to find a seat there.

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