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Discussion Starter #1
hi i am somewhat new to motorcycles although i do know a decent amount. so i have a honda c105t and when i got to start it air blows out of the carb, i took the air filter off just so i could spray starting fluid down the intake easier and when i kick it air blows out the top. I know one of my rocker arm springs is shot but shouldn't it still at least fire up the starting fluid? Could it be a spark issue? is it something to do with valves? i know nothing about valves or how to adjust or see if they need adjusting. i also know that my cylinder head gasket is pretty iffy and leaks oil so that could be an issue too? Do i not have enough compression? i was thinking maybe a top end rebuild?
 

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Air blowing back out the carb is not normal, and is possibly the intake valve not closing. All the other issues you mention indicates it may need a rebuild. It will probably cost more than the bike is worth if you have a shop do it - how handy are you with tools?
 

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Discussion Starter #3
I'm pretty good with tools and have everything I need I think. what does a rebuild entail besides new gaskets?
 

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Retired twice: Navy and as a govt contractor
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Do a compression test first. There is a lot of machine work involved in rebuilding a head properly.
 

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also when I take my valve covers off I can see them move up and down when engine cranks over.
If you can see them move, then you can check to see if there is a gap between the rocker arms and valve stems when they are 'up'. A feeler gauge will tell you how much gap there is, if any; if no gap exists, then adjust for some - too much is better than too little, and you are just testing here. Assuming there is some gap when cold, then do the compression test; if the valves aren't sealing, even with the gaps, the compression will probably be fairly low. That would also explain the blow back through the carb. As Critter says, you are probably in for a lot of work.
 

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Troublemaker
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If it is blowing back out the carb, it is not getting compression and will not fire with anything. The intake valve is not going shut to make compression.
 
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