Topic: Cb650 When to Shift

[jmonda]

I am fairly knew to riding and I recently purchased a 1981 cb650 anyway the tach on the bike is broken.  I was wondering if someone could tell me a good speed to be at to shift gear.  i.e shift into second@ 30, 3rd @ 45, 4th @50, 5th @65.  Any ideas would be helpful.  I know there will be a difference if you are wanting to get up to speed faster as well.  Ay help is needed.

[MickeyX]

I know with ours, it really depended on how well the bike was tuned. We can hit 70mph in 3rd gear with room to spare. Before a good carb tune and engine adjustments and tons of work to smooth it all out, our top speed was 55, downhill. 

If it's running pretty good and smooth, I think we shift into 2nd at 20 mph, used to be at 10-15. Then 3rd at 35-40mph. These SOHC4 bikes like high revs. Listen to the rev when you shift and then you can judge from there when you need to on the other gears. Or, you can put in a new/used tach. Should be the same part number on all these bikes...  '79-82 CB650 standard or Custom and '80-82 CB750 Custom only. 

Here's a buy it now on feebay for $35.50 for just the tach.
http://cgi.ebay.com/ebaymotors/Honda-CB650-CB-650-Tachometer-Tach_W0QQcmdZViewItemQQhashZitem5d2646951aQQitemZ400074118426QQptZMotorcyclesQ5fPartsQ5fAccessories

Or a speedo and tach instrument cluster for $45 (higher shipping though)
http://cgi.ebay.com/ebaymotors/1981-CB650-C-Instrument-Gauge-Cluster-Speedo-Tach_W0QQcmdZViewItemQQhashZitem20b04e460eQQitemZ140396873230QQptZMotorcyclesQ5fPartsQ5fAccessories

It depends on which way you want to go and if you want to fix it for the long term. 

[ieism]

Are you sure the tach is broken, and not just the cable?

[MickeyX]

You can test it by hooking it up to a power drill.

[jmonda]

Thanks for the info.  The bike is running pretty good an I have no problem hitting 85 out on the highway.  I have been keeping my eye on ebay. 

Yes I am sure the tach is broken it stuck over on about 7000 RPM and the needle i physically broken off so there is only about a quarter of it left and the other three quarters is sitting inside the tach.  I just have no idea if I am revving it to high when I get into it or not.

[jmonda]

wow ok.  Man I have to get a tach because I have no clue.  A bike is not like a car so I just have trouble and am so afraid of wrapping it out to tight.  Thanks and if anyone one lese has more to ad I am all ears.

[Frankenkit]

er.... 5th at 55 doing 4,5000.  I almost never get to use 5th, because only about 8 miles of my commute is highway and much of it has a 55 mph speed limit and enough commute traffic to keep us around 45mph.  I hit 70 this morning, though, in 5th, and I think I remember being closer to 5 or 5.5k rpms...  it's hard to remember the numbers, I just try to shift before 7.  

My bike doesn't sound as happy below 5k as it could be... but 4k is a nice, quiet, 30 mph neighborhood rpm. and I think that's 2nd gear, 30-35 mph at 4-4.5k rpms. 

I find it hard to hit 35-40 mph and be at a really good spot in my gearing... I'm either at the high fives in 2nd gear or around 4 in third gear, and I almost have to decide on whether I want the bike to be real smooth and maybe a little louder or need some finessing but be quieter.

At 5 it starts sounding a little tighter and at 6-7 it really sounds good.  Anything below 4 sounds a little boggy while riding... just no real torque.

but that could just be my bike, too.  "loud" is probably just my observation, I have stock 4-4 pipes and my bike is actually pretty dang quiet compared to most others... my love for quiet just comes from riding a bicycle for years before graduating to a motor.

[The_Crippler]

My first bike had a tach, and that's how I learned to ride.  Next bike did not, and I thought I'd be lost....that's when I learned how to ride by "feel."  This is my first bike since I was 18 that had a tach.  I don't know if I'll even remember how to use it.   

[Frankenkit]

the pointy thing goes 'round and points at numbers. There's a red (or white?) wedge around 9k.  Get real close to it without goin' into it.

[The_Crippler]

Thanks, Kit!  It's all so simple!

[jmonda]

Not sure what happened to an earlier post that gave me some info. I ride my bike to work everyday that I can.  I get on the highway where the speed is 70 mph and there is little traffic.  The speed limit is 70 mph for about 9 miles then it drops to 65 then 55 an so forth coming into town. 

My bike will get up to 85 no problem without me hammering through the gears.  However there are times I pull out on the highway and I am so cautious trying to climb it up to 70 quickly because I am afraid I am going to over do it.  It makes it difficult because this if my first bike other then offroad stuff.  I just do not have a feel for it at all.

I mean I do not even know what 5k feels like or sounds like on this bike

[cb650]

Power comes on at 5k and will fall flat at 9500.    I gues I lug mine around to much even though its overgeared.  I use 5th even at 50mph.   

[jmonda]

Thanks everyone for your help so far I appreciate it.  If anyone can pay attention kind of when they ride and know close to what speeds they shift to different gears let me know.  I know all bikes are different but this wold give me some idea.

[cb650]

Shift when it feels good.  Depends to much on conditions and what your doing.  If I'm putting around slow I might hit 2nd at 10mph but if I fell like a fast ride  wont see 2nd untill 50 or so.   

[jmonda]

Thanks that is hard for me to tell since I am a new rider.  I mean when I am putting around there is no problem but when I want to get into it that is when I have no clue

[cb650]

Well untill you get a tack shift a little early.  Engines are pretty bullit proof but I wouldnt do WOT in 1st for a mile.

[jmonda]

Thanks your right I am probably over complicating it

[Gordon]

Most people who aren't familiar with small 4cyl engines tend to think it's revving way too high when it's actually right about where it should be, so I think if you're going by feel you're probably being pretty conservative with the rpm's and don't really have much to worry about. 

[The_Crippler]

Shift when it feels good.  Depends to much on conditions and what your doing.  If I'm putting around slow I might hit 2nd at 10mph but if I fell like a fast ride  wont see 2nd untill 50 or so.   

I mean, it sounds overly simplified, but basically this.  It's a game of feel.  You'll get used to it the more you ride.

[jmonda]

Thank guys this has already been a huge help to me.  Eventually I get a tach on the bike and wont have to worry so much

[The_Crippler]

There's a phrase in homebrewing:  "Relax, don't worry, have a homebrew."  The mentality is that nothing ruins beer as fast as worrying about it.

So, relax, don't worry, go for a ride.   

[jmonda]

Thanks plan on doing that tomorrow