Cam timing chain install

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greenville
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Cam timing chain install

Post by greenville » Mon Feb 25, 2019 2:12 pm

Hi

My 89 FZR 400 recently snapped the timing chain and bent all the valves :cry:
I have got the head engineered with new seals new valves ect and have bought a spare motor which i have taken the timing chain out off
My question being - is it possible to fit the new timing chain without removing the crankshaft or splitting the motor?, dont want to remove the bottom end if not necessary. Any advise or perhaps a link to instructions would be appreciated

Evilchicken0
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Re: Cam timing chain install

Post by Evilchicken0 » Wed Feb 27, 2019 1:15 pm

You can use a soft link cam chain by clipping it onto the old one and hand turning the crank. Obviously you haven't got a chain in place so that can't be done. The drive cog on the crank doesn't have any way to attach a chain to it …. hmmm.

You've got the cylinder barrels and sump off the engine - you could get a couple of long cable ties and attach one of them to each end of the cam chain. Now feed each one through the chain tunnel and position the chain onto the gear cog. I don't know if this will work because of the captive chain guide or if theres enough access to the crank but its worth a look. If not you'll need to split the engine.

moforockband
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Re: Cam timing chain install

Post by moforockband » Sat Mar 02, 2019 10:35 pm

I dont mean to piss on your fire but all the soft shell bearings will be toast. They will have suffered major impact and will no longer hold even oil clearance.
I rebuilt an engine like this and it then ended up with a hole in the case. But the new top end was fine :)

hunter
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Re: Cam timing chain install

Post by hunter » Mon Mar 11, 2019 9:24 pm

You have snapped the timing chain once,
You have spent all that money on rebuilding the head and you want to fit a used timing chain :o

Evilchicken0
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Re: Cam timing chain install

Post by Evilchicken0 » Mon Mar 11, 2019 10:12 pm

hunter wrote:
Mon Mar 11, 2019 9:24 pm
You have snapped the timing chain once,
You have spent all that money on rebuilding the head and you want to fit a used timing chain :o
I think hes using a new chain but because the old one has gone he can't (easily) thread it onto the crank sproket

hunter
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Re: Cam timing chain install

Post by hunter » Wed Mar 20, 2019 9:48 pm

He states this in his post.
and have bought a spare motor which i have taken the timing chain out off

Evilchicken0
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Re: Cam timing chain install

Post by Evilchicken0 » Wed Mar 20, 2019 10:55 pm

hunter wrote:
Wed Mar 20, 2019 9:48 pm
He states this in his post.
and have bought a spare motor which i have taken the timing chain out off
Um ... ok you're right. On both counts.
Don't use a secondhand cam chain!!!

Brandon88
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Re: Cam timing chain install

Post by Brandon88 » Tue Oct 17, 2023 3:26 am

Hey,

Did you manage to replace that chain? I know this thread is 4 years old. My fzr400 timing chain has developed a rattle - need to replace it asap as I don’t want to end up with a broken motor. Any tips - I suspect it’ll be detailed in the service manual which is free online

MadMotoUK
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Re: Cam timing chain install

Post by MadMotoUK » Tue Oct 17, 2023 12:06 pm

It may not be the chain, check the tensioner first.

Brandon88
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Re: Cam timing chain install

Post by Brandon88 » Sat Oct 21, 2023 10:01 am

Turns out it's just a rattling exup valve.


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