clacking noise when open throttle in high gear

[flyingace]

haha ok as said before, the reason for keeping a lower rpm was because it was 85 degrees out and i wanted to keep engine temps to a minimum. i dont think its good for the engine to go 25mph in 2nd or 3rd gear for an hour or longer. id say thatd be around 3k with almost no airflow to the engine.

Yes, I think going 40 in 5th gear is better for the engine than going 40 in 1st.

[chef1366]

The engine will run hotter at lower RPMs.

[TheCafeKid]

The engine will run hotter at lower RPMs.

Correct, especially so on our lower oil pressure 8v motors. The oil is being pumped thru the motor obviously more slowly, therefore the motor itself will not be as cool.

[doctorgonzo]

Correct, especially so on our lower oil pressure 8v motors. The oil is being pumped thru the motor obviously more slowly, therefore the motor itself will not be as cool.

Riding around "town" with 30 and 40 mph speed limits I rarely hit 5th gear, maybe in a 40 zone. Driving mostly in 3rd and 4th.

[Nessism]

I will disagree somewhat with the other posters. An engine should never pre-ignite or 'ping' no matter how low the RPM. It should shutter, lug, shake, even die, but not ping. This indicates too low an octane gas, too lean a mixture or an intake leak - something is wrong.

My engine makes a similar clacking noise too when I roll the throttle at lower RPMs. After 12K miles, I think it's just the nature of the beast. But it doesn't ping. If yours does, fix it.

I agree! Engine should not knock except under severe circumstances. Check the ignition timing first and consider retarding it a couple of degrees. Also consider switching to a higher grade of fuel. Of course, this assumes the carbs are properly tuned and not running lean.

[TheCafeKid]

Before we go sending him scurrying looking for a problem that may or may not exist, lets CLARIFY exactly what PINGING is. the clatter that you are hearing, if its the same as mine does in the same circumstances, is NOT pinging. Pinging sounds like JUST what its called. You seem to be a smart person, i think you would know pinging. Just my opinion however.

[flyingace]

I saw three posts that referred to 'pinging' or detonation' on this thread prior to my post. I think that's adequate reason to correct the misconception.

[Dogma]

Riding around "town" with 30 and 40 mph speed limits I rarely hit 5th gear, maybe in a 40 zone. Driving mostly in 3rd and 4th.

This discussion has been very interesting to me. I often run about 35 (25 indicated) through level side streets in 5th gear, at 2000-2500 rpm. I'm just barely off idle at this speed, almost coasting. Any significant acceleration requires downshifting. My engine makes no funny noises at all, and never seems to struggle, running the cheapest gas.

But it sounds like I shift early, compared to most. In many 4-lane intersections around here, I'm often in 5th gear before I pass the other side of the intersection doing maybe 40. The bike easily pulls to higher speeds from there. But this is all just putting around town. Not really taxing the engine at all. This bumps my mileage from mid-30's to low 40's. More playful riding results in higher revs and lower mpg.

The only down side I see is the inability to accelerate in a tight spot. In those situations, more revs are of course a good idea. But why would I allow myself to be in a position where someone is going to run me over from behind? I'm still relatively inexperienced as a rider, but being always prepared for needing a sudden burst of acceleration seems like less situational awareness than I'm comfortable with. Off the top of my head, I can't think of a circumstance I should be in where I needed to keep higher revs just in case. I'd like to think I would recognize that situation when I see it though.

Does the MSF make recommendations on this in the advanced course? I've been reading Proficient Motorcycling, but Hough seems to talk mostly about being able to stop quickly. I don't remember a mention of being able to accelerate suddenly.

[doctorgonzo]

I think a lot is riding "style". I will on occasion "cruise" through town in 5th turning 2500 or so, and the bike runs fine (basically idling), as long as I don't need to accelerate because at that rpm in 5th cranking the throttle is going to lag, then bog, then finally start to pull after several seconds. I don't do that in traffic though. In traffic I want to be able to accelerate if I need to so it virtually never sees below 3500 rpm. If that means I'm driving a mile in 3rd or 4th gear, so be it. I think I'd consider myself a "moderately hard" rider. I generally shift about 4000 from 1st to second, then about 5000 to 6000 from then on. That's just normal riding, not "getting on it". If I'm out on the back roads having fun I'll do a normal shift at about 7000 and once in a while really get on it and shift near redline.

I'd add:
"I'd like to think I would recognize that situation when I see it though."
"That situation" is everytime a car is beside you. They start coming into your lane... my first reaction is to accelarate out of the way, not brake.

[spchips]

Looks like we hit another hot topic.

If this is the 1100G with the 8 valve motor, I'll bet it has the same air filter design as the 1000G and 850G. I wouldn't be surprised if the rubber seal was shot and it was leaking like mad. My 1000 did the same thing, and in traffic, it was BAD. Cruising around, usually didn't cause problems.

All of my bikes, if at 1000-2000 RPM, and smacked wide open, will detonate just enough to hear, until the RPM's come up. Riding in the appropriate gear is the best fix.


Check that AIR FILTER!!

[beachbum3478]

i actually re-sealed the airbox about two months, and wow did that make a difference.

[doctorgonzo]

i actually re-sealed the airbox about two months, and wow did that make a difference.

Yep, stock jetting is for very little air flow. It doesn't take much to bugger it up.