Restrictors

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cdfeto
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Restrictors

#1 Unread post by cdfeto »

Hi, just bought an RG50 a couple of weeks ago and have started to ride it around a bit, the bike was supposedly restricted to 50/60 km/h by a baffle, on the carby I assume? And it is also rev limited in the last three gears (4th, 5th and 6th) to about 7000 RPM, is that throught the CDI? The bike "tops out" at about 70 km/h, once again I assume its because of the rev limiter. Could the exhaust also be "baffled"?

Any information on these restrictions would be greatly appreciated.

pchast
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Re: Restrictors

#2 Unread post by pchast »

I underserstand why you are asking. But, as a new rider, should that even be a concern at this time?

Meanwhile, What do you rev it to when shifting? What did the dealer say when you asked about this?

Pete
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HYPERR
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Re: Restrictors

#3 Unread post by HYPERR »

cdfeto wrote:Hi, just bought an RG50 a couple of weeks ago and have started to ride it around a bit, the bike was supposedly restricted to 50/60 km/h by a baffle, on the carby I assume? And it is also rev limited in the last three gears (4th, 5th and 6th) to about 7000 RPM, is that throught the CDI? The bike "tops out" at about 70 km/h, once again I assume its because of the rev limiter. Could the exhaust also be "baffled"?

Any information on these restrictions would be greatly appreciated.
The little two smoke Gamma should easily rev to over 10,000rpm and easily go well over 100km/hr.

They made these in the mid to late 1980s didn't they? I'm shocked that nobody tried to destrict it in the last 3 decades! :shock:

The ringadings are usually restricted electronically and by the exhaust. Decorking an exhaust should not be too hard. I have no idea what methods they used to restrict it electronically so can't help you there. It must obviously know somehow that it is in the top 3 gears to destrict so I would start looking in that direction.
2008 Ducati Hypermotard 1100
2006 Kawasaki KLX250S
2004 Honda CBR600RR
2002 BMW R1150R
1996 Ducati 900SS

cdfeto
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Re: Restrictors

#4 Unread post by cdfeto »

I underserstand why you are asking. But, as a new rider, should that even be a concern at this time? Yes, I want to be riding a motorcycle, not a scooter/moped.

Meanwhile, What do you rev it to when shifting? What did the dealer say when you asked about this? 6000/7000 RPM

Would the CDI itself be programmed to restrict the sparks in the last gears? Could it be as easy as replacing the CDI?
As for the exhaust, would the restrictor be at the entrance (accessible) or in the actual exhaust?

cheers

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Re: Restrictors

#5 Unread post by flynrider »

Rev limiters are commonly built into the CDI. It's the best place to do the job. Given that, it's unlikely that such a limiter would only be activated in the top 3 gears. A simple CDI rev limiter merely cuts the spark to one of the cylinders when the rev count reaches a certain point. It would have no idea what gear you're in (unless it's a smart bike with lots of computer hardware).

My bikes CDI has a rev limiter that kicks in just above redline. It does that whether I'm overrevving in 1st or bumping off it in top gear at 135 mph.
Bikin' John
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