Tmax CVT Recall

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MrGrumpy
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Re: Tmax CVT Recall

Post by MrGrumpy » Mon Aug 19, 2019 3:24 pm

Ralph wrote:
Mon Aug 19, 2019 2:49 pm
Now I have never ridden a Tmax but I would think at 5500 rpm it would be close to max torque revs
so you open the throttle and this puts max torque on to the transmission forcing it into a lower gear,
as the revs rise and speed increases the and the transmission starts to change back up, I know you say
it does not want to go over 6000 revs but is the scooter still accelerating as you would expect? if
no acceleration then I would think you have a problem. neither would I expect any metallic noises.
I guess that at 5500rpm I've reached the top ratio of the CVT in normal operation, which I assume might be significant. Presumably a call for acceleration might cause the CVT to want to give a lower ratio to assist. To answer your question, No it does not want to accelerate at all from 5500 rpm - if you are gentle with the throttle you can persuade it to 6000 rpm eventually - too rapid acceleration will give you the nasty grinding noise. No idea what happens over 6000rpm as speeds are getting seriously illegal then!
It works fine up to 5500 rpm unless you want to overtake someone and twist the throttle too much...

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Ralph
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Re: Tmax CVT Recall

Post by Ralph » Mon Aug 19, 2019 3:57 pm

Do you think it's metal to metal or could it be a reanonce set up by the belt,
just running a few ideas passed you in the hope of helping.
Ralph
Nr Fleetwood
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bugsy
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Re: Tmax CVT Recall

Post by bugsy » Mon Aug 19, 2019 5:31 pm

Thanks for explaining in more detail.

As I understand it there is a moment before the higher revs actually transfer into acceleration. That doesn’t sound right.

Be interesting to know what she feels like after your work is carried out.

MrGrumpy
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Re: Tmax CVT Recall

Post by MrGrumpy » Tue Aug 20, 2019 5:03 am

Ralph wrote:
Mon Aug 19, 2019 3:57 pm
Do you think it's metal to metal or could it be a reanonce set up by the belt,
just running a few ideas passed you in the hope of helping.
Its possbile, but it sounds too much like metal to metal for comfort! Its quite a high pitched sound - interestingly its always the same (and constant) pitch.

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EvilRacer329
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Re: Tmax CVT Recall

Post by EvilRacer329 » Tue Aug 20, 2019 5:57 am

Can confirm that it's not just the CVT 'changing down' to give me more acceleration when the throttle is opened - it's a sudden snap up of 500-1000RPM followed my it snapping back down and then rising as normal. It feels exactly like what would happen if you were to pull the clutch in and then immediately let it go again on a geared bike - sudden spike in revs. I don't recall a metallic noise, but the three times it's happened so far it's caught me by surprise and I've been focused on the engine note. I'll be paying close attention during next week's trip...

Nick

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Re: Tmax CVT Recall

Post by MrGrumpy » Wed Aug 21, 2019 7:44 am

Well, I've had the new CVT installed, and so far, so good! No nasty noises and no 'revs but no drive' impressions. I even got to 6000 rpm without difficulty. I had to pay for the V-belt myself though (£112+VAT).
Bet they forgot to reset the V-belt trip meter......

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EvilRacer329
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Re: Tmax CVT Recall

Post by EvilRacer329 » Wed Aug 21, 2019 7:57 am

Well, I called Yamaha tech and they told me to talk to my dealer...but did suggest that they might cover issues out of warranty under certain conditions. I talked to my dealer, and they rarely get T-Maxes through, haven't seen this issue before but were more than happy to take a look and ask the question of Yamaha. If there are other case numbers etc. that I could use to prod them in the right direction, that would certainly help!

Who's your dealer, MrGrumpy? Taking it to the same place might be a simple way to avoid a lot of the arguments! :)

Nick

MrGrumpy
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Re: Tmax CVT Recall

Post by MrGrumpy » Wed Aug 21, 2019 10:06 am

EvilRacer329 wrote:
Wed Aug 21, 2019 7:57 am


Who's your dealer, MrGrumpy? Taking it to the same place might be a simple way to avoid a lot of the arguments! :)

Nick
Jax Motorcycles of York (contact Alan)

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EvilRacer329
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Re: Tmax CVT Recall

Post by EvilRacer329 » Mon Oct 07, 2019 4:45 am

Looks like I'm going to need to stop procrastinating and take action on this. Went for a couple of fast rides the last couple of weekends, and when the revs rise over 6k during overtakes the engine slips suddenly and dramatically up to 6.5-7k until I back off the throttle. My dilemma is as follows:

- My bike is out of warranty; expired before I bought the bike.
- I performed the most recent 6K service myself, because I'm a cheapskate.
- The bike now has 7k on the clock, and CVT belts are supposed to be replaced at 12k.
- The issue only occurs above 80mph on the clocks.

I could drop my bike off at my dealer, ask them to troubleshoot an issue at supra-legal speeds and then submit a request for a free repair under the "known CVT slipping issue" to Yamaha. If Yamaha say no, I'm on the hook for the diagnostic fees and still have an issue. Yamaha could even try to claim that it's just a side effect of the belt wearing, though that seems like a bit of a stretch.

The alternative, given that I'm reasonably sure that I've got the same problem as MrGrumpy, would be to order the parts at my own expense and just do the fix myself. I've torn engines down, swapping out a couple of pulleys shouldn't be too hard, although I shudder to think how much the parts are going to cost me. Then again, I saved money by buying used, and this is the sort of risk you take. I don't suppose someone has an invoice that could give me an idea on the cost?

Nick

MrGrumpy
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Re: Tmax CVT Recall

Post by MrGrumpy » Mon Oct 07, 2019 6:22 am

You can find the cost of Yamaha parts by looking on Fowler's website, and searching through the exploded parts diagrams, but make sure you have a store of your favourite sedatives at hand first!

https://www.fowlersparts.co.uk/browser/ ... rer/yamaha

Before Yamaha agreed to do mine, I consider ordering new parts myself and getting my local garage to fit them - but the prices for the CVT bits were too horrific to contemplate, at least until desperation sets in....


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