Check out this video of the sound my Grom makes when I start it. The idle immediately drops after that noise. It started after I removed my spark plug the other day. I screwed it back in and it is tight, not overtightened. I also put the black cap back on and it wont go on any further (I think), so I can't figure out what this is caused by.
Honda Grom Issue...
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Check out this video of the sound my Grom makes when I start it. The idle immediately drops after that noise. It started after I removed my spark plug the other day. I screwed it back in and it is tight, not overtightened. I also put the black cap back on and it wont go on any further (I think), so I can't figure out what this is caused by.
Thanks... Very helpful haha.
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forgot what it's called, but it sounds like the device that lowers the rpm after the engine is at a certain temperature. does the rpm drop after the same amount of time every time? or if it's colder, it takes a bit longer for the pop to happen then a drop in idle?
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My bike has been doing the same thing ever since I put the K&N filter on. Or maybe it's just more audible now that it's less restricted.
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Sent from my Note 2 using HondaGrom.net mobile app
Well it used to hold the higher rpms for a few minutes when warming up. But I never heard the pop sound before. Now it happens after like 2 seconds after starting it and as soon as the pop noise happens, the rpms drop. Does anyone else's Grom make that sound when the rpms drop after warming up?
I have a kn filter on now too. I never heard it before I put the filter on.
I just never noticed that noise before. Does yours make that noise when it cuts off?
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How many miles on your Grom ODM?
Removing and or replacing the spark plug should make no difference on the sound
I would take out the spark plug and check it for cracks or damage and check the spark plug gap.
If you have a compression checker I would check compression and is should be around 95 PSI which is not the true compression since according to BrianS there is a decompresser unit on the cam that reduces the compression on start up, READ BELOW
BrianS post on the issue
Guys,
Don't panic about the compression. It's about 160 PSI stock. The Grom has a ACR,(automatic compression release) on the exhaust rocker. Spinning the engine activates the weight on the cam and opens the exhaust valve just slightly. I don't know why they don't mention it in the shop manual. Using an intake rocker on the exhaust fix's the issue, and you get 160 PSI. It's there for starting.
Brian
good luck
Removing and or replacing the spark plug should make no difference on the sound
I would take out the spark plug and check it for cracks or damage and check the spark plug gap.
If you have a compression checker I would check compression and is should be around 95 PSI which is not the true compression since according to BrianS there is a decompresser unit on the cam that reduces the compression on start up, READ BELOW
BrianS post on the issue
Guys,
Don't panic about the compression. It's about 160 PSI stock. The Grom has a ACR,(automatic compression release) on the exhaust rocker. Spinning the engine activates the weight on the cam and opens the exhaust valve just slightly. I don't know why they don't mention it in the shop manual. Using an intake rocker on the exhaust fix's the issue, and you get 160 PSI. It's there for starting.
Brian
good luck
You lost me. It has 1048 miles or so. I don't know a thing about compression and what to look for or do with regards to that. Sorry haha. I will just hope it isn't that.
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Don't panic about the compression. It's about 160 PSI stock. The Grom has a ACR,(automatic compression release) on the exhaust rocker. Spinning the engine activates the weight on the cam and opens the exhaust valve just slightly. I don't know why they don't mention it in the shop manual. Using an intake rocker on the exhaust fix's the issue, and you get 160 PSI. It's there for starting
It's a mechanical unit on the CAM of the Grom that helps in startup, goes away after startup and compression goes up to 160 PSI
made a mistake on my post of 95 ft/lb should be 95 psi
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mine makes an audible noise. i'll try to listen if it's similar to what you hear.
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thanks for mentioning. this is the device that i couldn't remember the name of.
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Give thanks to BrianS who is doing all the research, cylinder 170cc upgrade, Grom port/polish upgrade, air-assist front fork upgrade and "REAL bearings upgrade to the swingarm instead of the rubber/metal cylinder sleeve". He is the one who sets the unknown about the Grom EZ for us to understand the concept of motorcycle engine and mechanical dynamics of a Grom motorcycle.
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check the valve clearance. it can cause the leak of compression and your idle rpm unstable. or if it is still in the range of non service try get a new spark pluge it sounds non sense but i have faced it myself that the spark pluge cause detonation problem even it is still new but the idle is no good. i change a new spark pluge and problem gone.
Sent from my GT-I9295 using Tapatalk
Sent from my GT-I9295 using Tapatalk
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Just noticed mine did the same thing this morning. I'm in Florida about 74 degrees.. Not worried about it.
Same popping sound and everything?
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