1986 Fj1200 engine knocking noise

[MarioR]

Hi Guys,

I found decent bike base that I would like to purchase and restore it.
1986 FJ 1200, around 38000 original km. Only concern that I have is engine sound. Idle is around 1100rpm and sound like a little bit of knocking at this rpm. When you raise rpm to 1200-1300rpm, noise is gone and does not reproduce when driving. I noticed UNI Pods filters and Kerker dual exhaust. Headers are single wall.
Not sure when oil engine was changed but looks dirty on the window revision. Not sure if this is top/bottom end noise or clutch. Millage looks original and documented. My FJ1100 does not have those noises. Should I be concern with those symptoms or this is normal?

Thanks guys for any help.

[FJmonkey]

Welcome Mario, that sounds like the starter chain noise. Quite normal, as the RPMs go up the chain does not slap. These air cooled engines are a little noisy. Get your valves checked, make sure none are too tight. You can check them with common tools. Changing them needs a special tool.

[Pat Conlon]

Welcome Mario, my simian friend is correct.....

[Bozo]

Agree with the starter chain being your problem.
A few years ago going home my FJ started to knock badly at one stage I suspected the bigends (yes it sounded that bad) but being over 150km from the next town I took a gamble and kept on going.
It didn't get any worse so I kept on going another 250km to home. I did read that the twin wall headers can be an issue so I started to check the No4 header, to cut a long story short it and others were loose. After tightening ALL the header clamps the bike ran perfectly,,,,no noise.

[Dads_FJ]

+2 on Starter chain.  I picked up an '89 with 59,000 miles last fall which had some starter chain noise.  All it took was a simple carb sync and I picked up the idle a tad to keep it from slapping around.

[MarioR]

Thanks guys for help and manual.

This make sense if starter chain doesn't have any tensioner.
Wondering, what is the cause of loose chain with such low mileage? Soft material, manufacture defect or maybe engine has another 100.000km on the dash unknown.... maybe some was using starter more that usual..?
Replacing chain probably will need splitting cases etc...which will bring restoration again up.

My friend has same bike with 90000km on the dash and engine sound and runs perfect.

[Pat Conlon]

http://www.fjowners.com/index.php?topic=19016.0

If you do decide to split the cases and replace the chain, also replace the oil jet with the new style.

[MarioR]

http://www.fjowners.com/index.php?topic=19016.0

If you do decide to split the cases and replace the chain, also replace the oil jet with the new style.

Thanks Pat.
This make sense. Where can I buy new oil jet and chain?
I will need to make a list for all parts needed for small overhaul like maybe bearings, seals etc.

[Pat Conlon]

http://www.fjowners.com/index.php?topic=19016.0

If you do decide to split the cases and replace the chain, also replace the oil jet with the new style.

Thanks Pat.
This make sense. Where can I buy new oil jet and chain?
I will need to make a list for all parts needed for small overhaul like maybe bearings, seals etc.

The banner at the top of the page will get you to the RPM folks...they will have all you need.

[aviationfred]

This is the Starter Clutch Oil nozzle that Pat has mentioned.

http://rpmracingca.com/proddetail.asp?prod=UpgradedOilNozzle&cat=39

I am pretty sure that you can remove the old one (#23 in the drawing), and install the upgraded nozzle by removing the alternator and bearing retainer (#20 in the drawing), with the engine still in the frame.

The photo with the Red arrow shows the Upgraded oil nozzle installed.




Fred

[aviationfred]

The old OEM nozzle (left) and the New upgrade nozzle (right).



Fred

[MarioR]

http://www.fjowners.com/index.php?topic=19016.0

If you do decide to split the cases and replace the chain, also replace the oil jet with the new style.

Thanks Pat.
This make sense. Where can I buy new oil jet and chain?
I will need to make a list for all parts needed for small overhaul like maybe bearings, seals etc.

The banner at the top of the page will get you to the RPM folks...they will have all you need.

Thanks Pat.

[MarioR]

This is the Starter Clutch Oil nozzle that Pat has mentioned.

http://rpmracingca.com/proddetail.asp?prod=UpgradedOilNozzle&cat=39

I am pretty sure that you can remove the old one (#23 in the drawing), and install the upgraded nozzle by removing the alternator and bearing retainer (#20 in the drawing), with the engine still in the frame.

The photo with the Red arrow shows the Upgraded oil nozzle installed.




Fred

Thanks Fred.
This is good tip, I will dig more into to it since it's shame to take apart low millage motor.
Hope this works.

[MarioR]

Coming back to the topic, does anyone know what is the cause of the chain on the starter stretch?
Is it manufacture defect that some model have this issue and others don't?

[Pat Conlon]

Starter chains stretch all the time, but they all don't make that god awful grinding noise unless there's an oil jet to rub on...
One time I bypassed my clutch safety switch, and thumbed the starter switch while my bike was in gear and my dumb ass was sitting on the seat... that did not help the starter chain one bit.