Bangs from exhaust at 3500rpm

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Hi guys,

I did another shotgun cleaning and this time used bit more air pressure and now all 4 cylinders start :)

Engine works bit rough and I noticed few things:
1. cylinder that did not work has lower temperature then other 3

2. I've took out air filter housing and checked how membrane parts move. On problematic cylinder there is 50% less movement when I rev the engine compared with other 3.

3. Here is the video that shows vacuum values at the moment. First gauge is connected to rear left (problematic) cylinder, second to front left, third to rear right and fourth to front right.
https://www.dropbox.com/s/bze4pwn0v7b8dbw/2016-09-13 16.33.52.mp4?dl=0

4. While engine was running I tried to change position of idle mixture screw in problematic cylinder and there was no change at all, even if I screw it all the way in or turn it out 3-4 turns.

5. There are no more bangs from exhaust.

Did not check valves but will check over the weekend.

He is alive but needs a red bull? :)


Vlada
 
Hi guys,

I did another shotgun cleaning and this time used bit more air pressure and now all 4 cylinders start :)

Engine works bit rough and I noticed few things:
1. cylinder that did not work has lower temperature then other 3

2. I've took out air filter housing and checked how membrane parts move. On problematic cylinder there is 50% less movement when I rev the engine compared with other 3.

3. Here is the video that shows vacuum values at the moment. First gauge is connected to rear left (problematic) cylinder, second to front left, third to rear right and fourth to front right.
https://www.dropbox.com/s/bze4pwn0v7b8dbw/2016-09-13 16.33.52.mp4?dl=0

4. While engine was running I tried to change position of idle mixture screw in problematic cylinder and there was no change at all, even if I screw it all the way in or turn it out 3-4 turns.

5. There are no more bangs from exhaust.

Did not check valves but will check over the weekend.

He is alive but needs a red bull? :)


Vlada
Your red bull is on the way and almost there.Should be any day now.
 
Synced all 4 carbs and engine work nicely now. :):):)
So it seems that only stubborn dirt in carbs was the problem.

Uhh finally. Thank you guys for all the help and ideas.


Can you tell me what is the procedure now?
Clean plugs and let engine run on idle for 10-20 minutes and check how plugs look like?
Then clean them again and ride for like 50km and check plugs again?


Vlada
 
Synced all 4 carbs and engine work nicely now. :):):)
So it seems that only stubborn dirt in carbs was the problem.

Uhh finally. Thank you guys for all the help and ideas.


Can you tell me what is the procedure now?
Clean plugs and let engine run on idle for 10-20 minutes and check how plugs look like?
Then clean them again and ride for like 50km and check plugs again?


Vlada

You were asking me for this----Go ahead and install the cops too.
 

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