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valve install?

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If I have to put in new intake valves due to piston being put in backward will I have to put in new valve seats or can I just put new valves in

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its always best to have the seats cut, but some people get away with just throwing valves in and going

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I am also operating under the assumption that the motor has some hours on it, and thats why u changed the piston.

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well i bought it used and it showed little wear just afraid of pin issue. Do you think I will have to replace the new piston I just installed? I only ran bike for like 5 min

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I responded to that in the other thread.. and thats the only real answer, but if I had to guess, I would think u can still use it..

Is the bike running shitty? do u think u bent valves?

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You need to take it apart again, and check for damage.

You may not even see if a valve is bent, it may be bent slight enough to not be seen by eye. You need to remove them and have them checked (measured) for straight stems, and the seats checked.

Valves and seats are either replaced and cut as a pair, or re-cut as a pair. Some do just plop new valves in, and go, but that is a hack job.

There is no safe way around it. Open it up and see if you even did the piston wrong. If you are sure of it, the head should be taken off and checked. The piston will show if contact was made, especially if you only put 5 min on it.

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The bike runs strong the only thing I noticed was backfire on deceleration. If it just marked the top of the piston do you think I will have to repalce the piston I just put in?

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Leakdown test will not work. Decompression system will allow the test to fail. If he even does a pressure test, it wont really let him now the amount of bend that will destroy his valves, valve guides and seats at less than 2-4 hrs of running time. The blue smoke might though.

Only right way is to remove, check, replace, ride.

If your piston is also marked up, yes, replace it. It may cause a hot, then weak spot, and can cause detonation and heat cracks later. Even if forged. I am not a piston crown expert, just going by read evidence.

If you open her up and see that type of damage, call Wiseco and ask.

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