Loud ticking or knocking sound in motor

[mad4106]

I brought my bike to Atv repair shop to install my big bore kit I have a stage 2 cam and the mechanic started it up it sounded like knocking when he started it he said it could be the wrist pin coming loose or the crank any other opinions. Also the bike doesn't even stay idling without giving gas

[CJM]

A 400ex will tick period, they all do-its the design of the valve train.

Does it sound like this: http://www.youtube.com/watch?v=41yVF96YiMI Thats with a hotcam and they are louder than a stock cam. But like I said they all tick

As for idling and starting. The carb is jetted too lean in both the pilot and main from the factory. Try a 40 or 42 pilot and up the main 1 size to a 150.

I guarantee the quad starts right up with the larger pilot or with very minimal gas.

[Thumpin440ex]

Or this kinda tick? my stg 3 sounds like a pissed off sewing machine, hahaha

http://www.youtube.com/watch?v=Gv9UfGlZN1M&list=UU0kSj9ypwIk660M3iqRBRhg&index=2&feature=plcp


People get scared but aftermarket cams have a more aggressive lobe, ramp rate then stock. Therefore it will have more valve train noise. :)


John

[Stickman400]

Originally posted by CJM
A 400ex will tick period, they all do-its the design of the valve train.

Does it sound like this: http://www.youtube.com/watch?v=41yVF96YiMI Thats with a hotcam and they are louder than a stock cam. But like I said they all tick

As for idling and starting. The carb is jetted too lean in both the pilot and main from the factory. Try a 40 or 42 pilot and up the main 1 size to a 150.

I guarantee the quad starts right up with the larger pilot or with very minimal gas. I think he would need a slightly larger main if he had them install a "big bore" kit. What kind of kit did you have them install mad4106? Was it a 406, 416, 426? Or was it an actual big bore like a 440 or 460 stroker? This will help us tell you what size of main to use.

[mad4106]

It currently has a stage 2 cam with wiseco 11:1 piston and it was ticking but now it got louder and it currently was smoking a lot I had to add a quart after every ride cause it burned that much oil but it didn't Have no problem idling until I went to start it before I brought it to the shop. The kit is a 440 big bore and I forgot to say I have a 450r carb

[Thumpin440ex]

So based on what your saying it has the normal tick of a ex, especially one with a bigger cam. The valves need to be adjusted about every 20 hours. Some do it sooner some do it longer then that. It probably needs valve seals and possibly a new rings. I would say valve seals first.


John

[mad4106]

If worst comes to worst and it is the crank should I stick with an oem one or get a hotrods hd one?

[2001400exrida]

run 100 octane minimum with the 11:1. You might be pinging.

[Thumpin440ex]

Originally posted by 2001400exrida
run 100 octane minimum with the 11:1. You might be pinging.


I would almost bet my quad on it as that not being the issue. 93 oct is enough for 11-1. If it was 12 that might require a mix of race, reg fuel..



If you do not plan to stroke it, I would personally go with a OEM crank again. Post a vid up of it running. Does it sound anything like the vids posted?



John

[mad4106]

It does sound sorta like the stage 3 hotcam video

[Ba9801]

Agreed with only needing 93 octane for 11:1. You should not have any problems unless your fuel is old as these newer fuels do not store well as the ethanol in them break down and lower the octane rating. I always try to run the quad on fresh fuel.

As for the noise a video of it would help alot but likely it is just the normal valve train noise from a larger cam.

As for the oil burning, I would check the valve seals & Valve guides. If you just had the big bore installed the rings should not be your problem.