How fast?

So do you think its jetting? When I go for it full throttle it starts popping and I get lots of hiccups. Could I just not be getting enough gas?
 
That's possible. I did a little work on mine the other day and then took it for a test blast. I broke the ton easily.
 
My plain jane stocker 81' Special seems to top out around 85-90. It has a PMA and a Pamco, otherwise bone stock.

My Black and White Rephased bike has been clocked at 127, with a bit more to give, but it was wild enough on a rigid. That one is rephased 277 degrees, 700cc's, Pamco and PMA with Lectron Carbs and Free Flowing Exhaust, Heavily ported heads, upgraded valve springs, and a 5th Gear OD. 17/32 Gearing... That bike LOVES to cruise at about 85 MPH....

Speed costs, how fast do you wanna go :laugh:
 
75-80 crusing speed not winding out running a 17-33 setup and it does have more but rough as shit pretty high rpms
 
Gearing plays a big part here too. Gear your 650 "to the moon" and you may turn a leisurely 3K @ 55 but you'll never pull redline in 5th. These are only around 50 HP bikes after all. To best match this engine's power characteristics, I like a 17-33 set-up using an 18" rear wheel, 17-32 with a 16". I have an extra 18" with a 32 on it. It noticeably deters take-off "lunge" in the lower gears and acceleration above say 75 in 5th.
 
Mine has done 85 on a trailer!

About 70 is all there was room for up in the hills when she was running in the late 80's. She had more. Probably still does, but I have another bike for that.
 
Yeah the motor is freshly rebuilt and timing is good. the bike runs great and has an easy cruise at around 60 to 65 but when I try to give it a little more it starts popping
 
Any stock XS650 with stock exhaust,stock carbs, stock air box and stock air filters will do 100 mph, as long as it has proper gearing as 5twins mentioned. The 17/33 gearing seems to be a nice combination.

I had an XS500C (bought new in 1976), and they would also do the TON, easily.

Any XS650 that will not do the TON, is an embarassment to the mark, and I say learn to tune your carbs and install a decent ignition.

Personally I never exceed 110 Km/hr or 68 mph; to do so would be tempting the long arm of the law to reach out and nab me:D
 
My 1980 with 17/33 gearing, 120/90-18 rear tire, front brake :D fresh top end with stock bore/stroke/cam/TCI/Mikes' 2 into 1/210 pound redneck and pods will easily do 95 with a bit more to go. I think 105 is easily doable tucked in on flat ground.

Not that I advocate such foolishness. :p
 
So catastrophe 's question seems to be; is something wrong with my bike? I think yes is a good answer. Now if he will give us some details of what he's got, filters, carbs, exhaust, jetting compression tested, valves set? there may be some hints as to what to look for.
 
gggGary said:
So catastrophe 's question seems to be; is something wrong with my bike? I think yes is a good answer. Now if he will give us some details of what he's got, filters, carbs, exhaust, jetting compression tested, valves set? there may be some hints as to what to look for.
Click to expand...

I concur.

I've only had the testicular fortitude (and safe opportunity) to run low 90s but I felt like it had enough left to push over 100. I can very easily hit over 70, and have without realizing, so yes, something isn't right if you're unable to do much more than 65.

~ Derek
 
I've had my 80 special with pod filters and shorty mufflers up to 90 and I still had a bit before redline, would think I could have hit 110 if I kept pushing, but might have blown up also.
 

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