Problems after cam and head gasket swap

MeatHammer · 05-18-2021, 01:06 PM

I changed out the camshaft and put a thin head gasket on my x22R (69mm bore engine). I went to fire it up and it seems like I have zero compression and it is making a clanking sound when turning over. Something is definitely not right. I have timing dialed in and everything was put together by the factory service manual. Any ideas of where to start looking

**JerryHawk250** · 05-18-2021, 01:12 PM

Check the timing chain tension. I would also recheck cam timing. I always turn the engine over by hand to verify clearance before actually trying to start it.

What cam did you end up putting.

MeatHammer · 05-18-2021, 01:20 PM

Quote:

Originally Posted by JerryHawk250

Check the timing chain tension. I would also recheck cam timing. I always turn the engine over by hand to verify clearance before actually trying to start it.

What cam did you end up putting.

I put the cam that came with the big bore kit I bought. It’s a Chinese kit so no specs on it. When I am at tdc both valves should be closed correct?

**JerryHawk250** · 05-18-2021, 01:39 PM

Quote:

Originally Posted by MeatHammer

I put the cam that came with the big bore kit I bought. It’s a Chinese kit so no specs on it. When I am at tdc both valves should be closed correct?

Yes the both should be shut. I can't imagine you're having a valve clearance issue but depending on how aggressive the lobes are on the cam it could be possible. It could be slack in the timing chain. Check that the tensioner is actually putting tension on the chain.

MeatHammer · 05-18-2021, 01:50 PM

The cam definitely had a lot longer duration on both lobes. My next plan was to put the original in and see what happens

MeatHammer · 05-18-2021, 03:26 PM

Quote:

Originally Posted by JerryHawk250

Yes the both should be shut. I can't imagine you're having a valve clearance issue but depending on how aggressive the lobes are on the cam it could be possible. It could be slack in the timing chain. Check that the tensioner is actually putting tension on the chain.

I just looked back to the post I made about the kit I bought and you had said that the cam looked pretty aggressive. Maybe it’s too much. I am ordering a hot cam to compare it with.

MeatHammer · 05-20-2021, 03:42 PM

I got my Hotcam today and it is definitely very mild compared to the Chinese one I put in. Compared to the cam that came from the factory there is very little difference in duration and lift. Hopefully the hot am works and gives me some gains

Mudflap · 05-22-2021, 03:54 PM

Any chance the head gasket is a tad too small? If its even 1 mm too small the edges of the piston can make contact.

MeatHammer · 05-23-2021, 11:34 PM

Quote:

Originally Posted by Mudflap

Any chance the head gasket is a tad too small? If its even 1 mm too small the edges of the piston can make contact.

I am pretty sure you are correct. Pulled the head and can see a slight indentation mark on the outside edge or the combustion chamber. I am going to double up the gasket and put it back together. Thankfully I ordered a few extra (thin)head gaskets.

MeatHammer · 05-25-2021, 01:40 AM

It’s alive! Mudflap was right, the gasket was too thin. I doubled up the gasket and everything is working great. In fact it sounds better than before. Can’t wait to ride it again. Thanks everyone for all the help!

Kurticus · 05-26-2021, 01:33 PM

That probably what's wrong with my big bore kit I used the TBOLT thin gasket instead of the big fat OEM head gasket.thats why my Vader was make Ng the pinging sound I'll try to fix it tonight

franque · 05-26-2021, 03:39 PM

Always, I repeat always, turn the engine over by hand after it has been reassembled. You could have easily avoided this and potential damage to the valves, cylinder, piston, and cylinder head by turning it over with a socket on the crank.

MeatHammer · 05-28-2021, 01:18 AM

Quote:

Originally Posted by franque

Always, I repeat always, turn the engine over by hand after it has been reassembled. You could have easily avoided this and potential damage to the valves, cylinder, piston, and cylinder head by turning it over with a socket on the crank.

I turned it over many times with a ratchet and never heard the piston hitting the cylinder head. Even after I started it and realized I had a problem I couldn’t get it to make the noise by hand cranking or even using the starter.

TxTaoRider · 05-28-2021, 06:14 AM

If you use the stock head gasket, make sure it's not too small for your big bore kit. Set it on there and make sure it doesn't protrude into the cylinder area. That can cause a new set of problems from hot spots to not sealing correctly.

05-18-2021, 01:06 PM	#1
MeatHammer Join Date: Apr 2020 Posts: 67	Problems after cam and head gasket swap I changed out the camshaft and put a thin head gasket on my x22R (69mm bore engine). I went to fire it up and it seems like I have zero compression and it is making a clanking sound when turning over. Something is definitely not right. I have timing dialed in and everything was put together by the factory service manual. Any ideas of where to start looking
	0

05-18-2021, 01:12 PM	#2
JerryHawk250 Moderator Join Date: Oct 2016 Location: Houma, La. Posts: 11,591	Check the timing chain tension. I would also recheck cam timing. I always turn the engine over by hand to verify clearance before actually trying to start it. What cam did you end up putting. __________________ 2023 Lifan Lycan 250 Chopper 2023 Venom Evader 2022 Lifan KPX250 2020 Kawasaki Vulcan S (Sold) 2004 Honda ST 1300 2016 Black Hawk 250 (sold) Keihin PE30 carb,125 main,38 slow.Pod filter,ported & decked head 10:1 CR,Direct Ignition Coil,15/40Sprockets,NGK DPR8EIX-9,De-Cat,Dual Oil Cooler,Digital Cluster 2016 Cazador180 XL 2014 Coolster150 JerryHawk250.com My YouTube Channel
	0

05-28-2021, 06:14 AM	#14
TxTaoRider Join Date: Oct 2020 Location: Flower Mound Texas Posts: 904	If you use the stock head gasket, make sure it's not too small for your big bore kit. Set it on there and make sure it doesn't protrude into the cylinder area. That can cause a new set of problems from hot spots to not sealing correctly. __________________ 2021 Tao Tbr7 - "Lucille" Mods so far- Brozz swingarm, 21" front rim (Bridgestone Tw302 rear/Dunlop D606 front tires), Digital gauge cluster, pz30b pumper carb, after market hand guards, aftermarket brake and clutch levers, round fold away mirrors, Fly handlebars shortened slightly, 13t front sprocket 2009 Q-link Legacy 250 1982 Suzuki GS1100ES - "Jolene"
	0

05-18-2021, 01:50 PM	#5
MeatHammer Join Date: Apr 2020 Posts: 67	The cam definitely had a lot longer duration on both lobes. My next plan was to put the original in and see what happens
	0

05-20-2021, 03:42 PM	#7
MeatHammer Join Date: Apr 2020 Posts: 67	I got my Hotcam today and it is definitely very mild compared to the Chinese one I put in. Compared to the cam that came from the factory there is very little difference in duration and lift. Hopefully the hot am works and gives me some gains
	0

05-22-2021, 03:54 PM	#8
Mudflap Join Date: Sep 2014 Posts: 1,894	Any chance the head gasket is a tad too small? If its even 1 mm too small the edges of the piston can make contact.
	0

05-25-2021, 01:40 AM	#10
MeatHammer Join Date: Apr 2020 Posts: 67	It’s alive! Mudflap was right, the gasket was too thin. I doubled up the gasket and everything is working great. In fact it sounds better than before. Can’t wait to ride it again. Thanks everyone for all the help!
	1

05-26-2021, 01:33 PM	#11
Kurticus Join Date: Nov 2020 Posts: 18	That probably what's wrong with my big bore kit I used the TBOLT thin gasket instead of the big fat OEM head gasket.thats why my Vader was make Ng the pinging sound I'll try to fix it tonight
	0

05-26-2021, 03:39 PM	#12
franque Join Date: Nov 2017 Location: Marseille, France -> Conakry, Guinea Posts: 1,481	Always, I repeat always, turn the engine over by hand after it has been reassembled. You could have easily avoided this and potential damage to the valves, cylinder, piston, and cylinder head by turning it over with a socket on the crank.
	1