Nmax shuddering

[1happykamper]

Good morning! My 2023 Nmax with only 7k km starts just fine first thing in the morning. But moving is another story 

 

A huge shuddering occurs before the bike starts to move... Then everything is fine. Until I stop... Then.. Shuddering again. 

 

 

It feels exactly like a manual clutch in a car that's not engaging correctly 

 

I took it to the Yamaha dealer today but they are too busy. Come back tomorrow 

 

A comment the dealer made was that he's seen this problem before with fat men. Thai directness 555. I'm 187 cm and 105 kg. Is this cause legit? 

 

Can the belt.. CVT?.. can it be adjusted? Or new normally needed? 

 

EDIT.. but when the bike is normal temperature everything is smooth again on take off. 

 

 

[Agusts]

It's the auto clutch at the back of CVT, the clutch shoes and clutch housing bell. Though it's very rare in Yamaha..., but I have seen this on almost every heavy Honda scooters, ADV 350 and Forza 300/350...

 

I myself and 2 other friends all currently have this issue. Dealers just open and clean it, problem comes back after a few weeks. On my previous Forza I have used aftermarket Bell and Carbon shoes, it worked perfectly for 25,000km, then one shoe broke, changed back to OEM shoes and worked perfectly until I sold it. 

 

Just yesterday ordered aftermarket Bell to change on my current Forza. This time I am leaving the OEM shoes and not changing it. I think changing the Bell alone resolves it - will see... 

 

As you have warranty, have to play with what Yamaha says, maybe ask them to change shoes and bell to OEM on warranty, it should work for another 7000 km...! 

[VocalNeal]

3 hours ago, 1happykamper said:

Good morning! My 2023 Nmax with only 7k km starts just fine first thing in the morning. But moving is another story 

 

A huge shuddering occurs before the bike starts to move... Then everything is fine. Until I stop... Then.. Shuddering again. 

 

 

It feels exactly like a manual clutch in a car that's not engaging correctly 

 

I took it to the Yamaha dealer today but they are too busy. Come back tomorrow 

 

A comment the dealer made was that he's seen this problem before with fat men. Thai directness 555. I'm 187 cm and 105 kg. Is this cause legit? 

 

Can the belt.. CVT?.. can it be adjusted? Or new normally needed? 

 

EDIT.. but when the bike is normal temperature everything is smooth again on take off. 

 

 

 

Dust in the clutch. It needs a good high speed run at 80 kph and over to blow out all the dust.

[1happykamper]

80 kph? I'll pee myself. Sixty is my top speed 😂😂😂

 

I'll get in a highway tomorrow. Try that. Worth a shot. Thanks 

[VocalNeal]

On 5/15/2025 at 2:58 PM, 1happykamper said:

80 kph? I'll pee myself. Sixty is my top speed 😂😂😂

 

It sounds like your riding style could best be described as ? relaxed. This could result in the clutch facings becoming glazed. 

 

Your clutch could also do with a few aggressive accelerations from a stand still.  Find a deserted space of road and do a few full throttle pull aways from a standstill. Up to you 60 kph comfort zone will do for this. 

[Agusts]

Or you can hold both brakes strong, then rev the throttle to about 4k or 5k for a a couple of seconds, do it 2 or 3 times....

 

Or open the clutch, clean and sandpaper the shoes... 

 

But all of these only fix it for a few days, after that it will be back again. Been there done that...! 🙄

[Agusts]

My clutch housing bell arrived today, I used this on my previous Forza. 

 

The small holes and groved inside the bell which are added to the standard (Honda) bell makes it a lot better, small holes stop it getting warm an warped, also exit resin/dust. The groves catch the shoes, stop it slipping...