Scooter won't go past 6000 RPM when riding By t84a (Read 13,904 times)

[t84a]

It will rev over 8k on center stand but won't rev past 5900-6000 when riding, even down hill.  I've adjusted the valves and replaced the carburetor.  It has to be a driveline issue, right?  Suggestions?

[Alleyoop]

Yes I would say the problem is probably in the Weights they are to heavy. So take the Variator off and weigh the weights. By the way What scoot is it a 50cc a 150cc a 250cc etc and what engine does it have Look on the case by the sidestand it will be itched on the case there.
Alleyoop

[t84a]

161QMK
Marketed as a 200 but it a 169cc GY6.

[dmartin95]

Jan 15, 2015 12:34:31 GMT -6 Alleyoop said:

Yes I would say the problem is probably in the Weights they are to heavy. 
Alleyoop

How would the weights be "too heavy"?

Unless he installed some after it came from the factory, shouldn't it have the right weights from the factory? ( <-- This is a question, not a prelude to a debate)

----------------------------

I don't know all that much about how the trans works, just yet.... But I do have a basic understanding and some times your rollers will develop flat spots or your clutch springs can wear... This can cause your ratio's not to climb and sometimes climb too high, too fast.... 

[Alleyoop]

Normally the weights they put in at the factory are actually to heavy and limit the top end and rpms.

In addition the carbs come set really LEAN to passs emissions.

As for rollers developing flat spots that would actually create higher rpms and less top end.
Alleyoop

I wrote up about the CVT here:

scooterdoc.proboards.com/thread/7633/variator-weights-contra-clutch-springs

[jct842]

Low air in tires can also effect speeds as it is resistance, uphill, down hill, and on the level.

[t84a]

I'm not convinced it's the weights just yet because my scooter is slow as well. I'm leaving probably 10 mph on the table. I'm thinking maybe it's the clutch. The scooter has less than 50 miles on it. 

[dmartin95]

Jan 15, 2015 12:21:11 GMT -6 t84a said:

It will rev over 8k on center stand but won't rev past 5900-6000 when riding, even down hill.  I've adjusted the valves and replaced the carburetor.  It has to be a driveline issue, right?  Suggestions?

I got to thinking about your question and was wondering if you could provide a little more background info on the scooter... Is it new? Why did you replace the carb? Was it the same size carb? 

Also, is this a new problem?

[Alleyoop]

Jan 15, 2015 14:49:49 GMT -6 t84a said:

I'm not convinced it's the weights just yet because my scooter is slow as well. I'm leaving probably 10 mph on the table. I'm thinking maybe it's the clutch. The scooter has less than 50 miles on it. 

If your RPMS are low it will be SLOW.

[cyborg]

i'm with Alley on this one,,,,AGAIN,,,,,,,i'd be going to lighter weights

[t84a]

Thanks for the replies. Are people using a variator tool to hold it to remove the nut? If so, which tool.

[jerryscript]

Get yourself an impact wrench, much quicker/easier to use, and can be used for other projects around the house. I use this one from Harbor Freight, it's 12v so I can hook it right up to the scooter battery. It's the wind up and release type, so it spins then whacks the nut. Usually takes 2-3 whacks to remove, and I let it whack it 3 times when I re-install the variator nut. I actually carry it and a spare belt with me, so I can switch out the belt on the side of the road if it happens to fail. One of the variator tools will cost you $10-20, this is on sale now for $22.99, and can be used for so much more!

Harbor Freight 12v Impact Wrench

[rks]

Jan 15, 2015 15:04:24 GMT -6 dmartin95 said:

Jan 15, 2015 12:21:11 GMT -6 t84a said:

It will rev over 8k on center stand but won't rev past 5900-6000 when riding, even down hill.  I've adjusted the valves and replaced the carburetor.  It has to be a driveline issue, right?  Suggestions?

I got to thinking about your question and was wondering if you could provide a little more background info on the scooter... Is it new? Why did you replace the carb? Was it the same size carb? 

Also, is this a new problem?

Less than 50 miles....Carburetor has been replaced.....I would bet this is where your problem lies.

[JoeyBee]

It is going to be a combination of both the carburetor and variator weight. At stock my 150cc wouldn't pass 6000RPMs. No matter what.

But first after installing a tunable carburetor, rejetting, and following Alley's guide it raised to 7000RPMs. Next I changed my weights from 13grams to 12grams, I top out just below 8000RPMs. I am very happy with the results and how she runs.

[t84a]

Jan 16, 2015 6:56:58 GMT -6 JoeyBee said:

It is going to be a combination of both the carburetor and variator weight. At stock my 150cc wouldn't pass 6000RPMs. No matter what.

But first after installing a tunable carburetor, rejetting, and following Alley's guide it raised to 7000RPMs. Next I changed my weights from 13grams to 12grams, I top out just below 8000RPMs. I am very happy with the results and how she runs.

Well, I'm not just looking to raise the RPMs. I need more top speed. It accelerates fine. I upgraded to a better carb so I'm not sure what rks is implying. 

Where is this "Alley's guide"?