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I have an issue where the engine runs fine on one start up but develops a noticeable valve tappet noise on another start up. No linkage to fuel that I can tell. I always use premium. Could a dragging starter motor or cam chain tensioner cause this? A stethoscope has pretty much set the location in the valve train. Any help w be appreciated.

Changed the oil recently?

Yes. Changed every 1,000 mi w Redline 10w30 and new filter.

How many miles on the engine?

Where are you?

Forza 300?

By the way, you are changing the oil way too often. Every 8,000 miles is perfectly adequate.

And Regular gas is the recommended fuel.

There's 3,500 mi on bike and engine....Forza 300. I change oil often as it's usually cheap insurance against major problems.....especially when we're only talking about a quart and a half. As far as fuel, the manual calls for 91 octane which is premium here (California). The intermittent nature of the problem is what is confusing. One time it starts w no tappet noise and another time it starts with it. No difference if it's hot or cold, first start of the day or second or third. I'll be tearing it down to check clearances just to be safe but I was hoping someone on the board had seen this problem and could shed some light on it.

Manual calls for 91 RON which is 87 (R+M)/2 which is what USA pumps have if you read the fine print. Or USA Regular.

Actually it will run on almost anything, I have tried them all and it makes no difference. The wind speed and air temperature make a bigger difference.

Changing the oil frequently makes very little difference to the engine but it means you are LOOKING at the motorcycle carefully which is a good thing. Waste of money and pollutes the world more.

I am hearing impaired so I would probably never hear your noise. The Forza is a relatively cheap scooter. It is not worth spending a lot of money to fix minor problems. Ride it until it breaks. Fix it if you can. Buy something else if you can't.

It is way too easy to spend money and time chasing a problem that is not really a problem.

Check your brake pads because Honda is too cheap to put $1 worth of lube in the callipers. Hell they forgot to put oil in my forks, !@#$%^&*.

I too have been faked out by that 91 RON thing. It would not have cost Honda much to put "(or 87 octane in USA and Canada)" in that paragraph.
http://www.pencilgeek.org/2009/05/octan ... sions.html

Thanks for the feedback davenowherejones. I did not recognize the octane discrepancy.

davenowherejones wrote: It is way too easy to spend money and time chasing a problem that is not really a problem..

Your water pump still dribbles a little?

E. Foster Salsbury wrote:

davenowherejones wrote: It is way too easy to spend money and time chasing a problem that is not really a problem..

Your water pump still dribbles a little?

Too scared to look. I need to clean the underside of my Forza and look. It is really dirty down there and I really do need to look.

I am a newby and was in a hurry to get this question on board. This thread should probably be in the Forza 300 Technical section. Can Modsquad perform this function? If so, Thank You.

Does the Forza have one of those Variable Timing Devices that could have an intermittent issue at startup's idle ? After startup on idle and the intermittent problem is evident - if the engine revs a bit, does the problem remain when it drops back down to idle ?

these engines use solid lifters meaning they are metal to metal contact. by virtue of this design a tapping noise is to be expected especially upon first morning cold engine starts . After oil pressure builds and engine warms the metal to metal tolerances will change and once the oil is flowing usually this tapping is cushioned to where it quiets down the metal to metal tapping. If it doesn't go away or change to quieter running check your oil psi. If it taps on a warm engine start the oil viscosity could be suspect or the oil filter drain back valve may be an issue. Replace oil with heavier grade, and new oil filter. Also use a moly additive oil ..See what happens.

BruttoBestia wrote:There's 3,500 mi on bike and engine....Forza 300. I change oil often as it's usually cheap insurance against major problems.....especially when we're only talking about a quart and a half. As far as fuel, the manual calls for 91 octane which is premium here (California). The intermittent nature of the problem is what is confusing. One time it starts w no tappet noise and another time it starts with it. No difference if it's hot or cold, first start of the day or second or third. I'll be tearing it down to check clearances just to be safe but I was hoping someone on the board had seen this problem and could shed some light on it.

Yeah, don't worry about critics of frequent servicing practices -
Saw a bumper sticker, "Everyone in entitled to my opinion."
I let 'em slide right off my back....I'm sure you do, too!

Fish

BruttoBestia wrote:I have an issue where the engine runs fine on one start up but develops a noticeable valve tappet noise on another start up. No linkage to fuel that I can tell. I always use premium. Could a dragging starter motor or cam chain tensioner cause this? A stethoscope has pretty much set the location in the valve train. Any help w be appreciated.

Yes and yes.
Un-disengaged starter makes a hellish noise, so if its a quieter tapping noise the more likely culprit is the camchain tensioner.
See if starting it on the centrestand and giving it a few gentle revs as it warms up will make any difference.

Could also be incorrect oil level.
The more you change the oil the higher the chances of getting the oil level wrong.
In your case wrong oil level is 800% more likely.

A Scotsman told a joke ?
!!


Fish

BruttoBestia wrote:I am a newby and was in a hurry to get this question on board. This thread should probably be in the Forza 300 Technical section. Can Modsquad perform this function? If so, Thank You.

Sure! Sorry I missed your earlier request. Thread moved. Good luck with your tapping noise Brutto

fish wrote:A Scotsman told a joke ?
!!


Fish

An American walked into a bar.
OUCH!!
It was an iron bar.

Springer 1.....The tapping noise is present on one start up but not on the next. When it does tap, it follows the rpm from idle to higher rpm. I know of no variable valve timing with this engine. Thanks for the help.

Easyrider & GN2.......I use 10W30 Redline Motorcycle oil and I measure the oil w a measuring cup and tend to put maybe 10 ml under the recommended levels. Redline is supposed to have one of the highest levels of molybdenum(sp). I guess it would be a cheap troubleshooting technique to try a 10W40 upgrade and see what happens. Thanks to you both for your input and advice.

Springer 1.....The tapping noise is present on one start up but not on the next. When it does tap, it follows the rpm from idle to higher rpm. I know of no variable valve timing with this engine. Thanks for the help.

OK so that’s not it - and I doubt that oil viscosity would cause an intermittent issue that clears up on a restart - same with the cam chain tensioner or fuel quality - how could it be intermittent? So what remains? ..... possibly an intermittent ignition timing or fuel injection issue that could cause something like pre-ignition (pinging). But really - I’m stumped and would need to take it to a dealer if it were mine. Sorry, it’s above my pay grade.