• Welcome to Jetboaters.net!

    We are delighted you have found your way to the best Jet Boaters Forum on the internet! Please consider Signing Up so that you can enjoy all the features and offers on the forum. We have members with boats from all the major manufacturers including Yamaha, Seadoo, Scarab and Chaparral. We don't email you SPAM, and the site is totally non-commercial. So what's to lose? IT IS FREE!

    Membership allows you to ask questions (no matter how mundane), meet up with other jet boaters, see full images (not just thumbnails), browse the member map and qualifies you for members only discounts offered by vendors who run specials for our members only! (It also gets rid of this banner!)

    free hit counter

Do all 1.8L shake?

ReelFishingSWFL

Well-Known Member
Messages
82
Reaction score
43
Points
57
Boat Make
Yamaha
Year
2017
Boat Model
FSH Sport
Boat Length
19
I was told by my mechanic not to worry about my 2017 1.8l HO shaking at idle.. he stated that all 1.8L have that shaking and it’s completely normal. New plugs I put them in today just odd shakes but runs fine..
 

906Tony

Jet Boat Junkie
Messages
214
Reaction score
477
Points
137
Location
Escanaba Mi.
Boat Make
Yamaha
Year
2017
Boat Model
AR
Boat Length
24
Yes the 1.8L‘s do have a bit of a shake at idle. Totally normal. I’m guessing it has to do with a slightly aggressive cam profile built more for top end performance. Once you elevate the rpms they smooth right out
 

FSH 210 Sport

Jetboaters Admiral
Messages
6,022
Reaction score
7,073
Points
437
Location
Tranquility Base
Boat Make
Yamaha
Year
2020
Boat Model
FSH Sport
Boat Length
21
Yes the 1.8L‘s do have a bit of a shake at idle. Totally normal. I’m guessing it has to do with a slightly aggressive cam profile built more for top end performance. Once you elevate the rpms they smooth right out
More valve overlap helps with clean out and more power but makes for a more rumpty idle. If you’ve ever been around a V8 thats been tuned up with .500” lift cams with a lot of overlap you know the sound.

Go to 1:21 for the idle
 
Top