Closed Throttle Riding Without Clutch

[gasgas]

hi all, bike is a pro 250 2002.

i can not ride my bike idle on the tarmac(level ground) without using a little clutch slipping. It starts jerking and popping the chain when i try it without the clutch. Be noted it is only with closed throttle riding, the minute i open it further it cures itself.

Is this familiar?

I don't find it a problem, but was just wundering that because of the big flywheelweight etc it shld be possible to do it without using/feathering the clutch.

[coxy]

try turning the tickover up a little see if that helps to smooth it out a bit

[gasgas]

yep, offcourse that wld smooth it out, it is the same as opening the throttle a bit. I just guess big flywheel, 2stroke, smooth ride at minimum throttle. Obviously not

[scorpa3]

My Scorpa does the same thing. Take a look at the chain tensioner, mine has a fit when I try this.

[mattr]

i can not ride my bike idle on the tarmac(level ground) without using a little clutch slipping. It starts jerking and popping the chain when i try it without the clutch. Be noted it is only with closed throttle riding, the minute i open it further it cures itself.

<{POST_SNAPBACK}>

You indicate this is at full closed throttle right? My bike will chug along in 1st gear with closed throttle (idle only) and feel choppy like you indicated. If I did this in a higher gear like 2nd or 3rd, the motor would probably stall. When riding at closed throttle in a section, I am always lightly slipping the clutch to smooth the power transfer and/or cracking the throttle open slightly. Note: if I tried this on my enduro bike, the engine would easily stall in any gear. I think the only reason you get away with it on a trials bike is the heavier flywheel.

[woody]

OK, my opinion. Modern trials bikes (which covers the last 10 or more years) aren't made to ride on the throttle slowly at very low revs any more. They're designed to produce quick bursts of power and to be ridden in a point and squirt technique on the clutch and brakes which is the modern technique - although it doesn't suit everyone obviously, me included. The days of riding clutch out on the 2 strokes, old Bultaco/Ossa/Montesa style is generally gone. Those bikes had big ignition flywheels as well as clutch flywheels and that allied to softer engine porting meant they could comfortably chug below walking pace clutch out, with no snatch or jerkiness. Modern bikes with their much lighter flywheels, more radical porting (and very bouncy suspension) don't lend themselves to that style of slow clutch out riding. Exceptions are the Rev 3 with their 3 stage ignition which are very progressive off the throttle and the Scorpa which is a bit softer than most but still lumpy to a degree.

As far as your bike is concerned I'm assuming when you talk about heavy flywheel weight you mean it in the general sense that trials bikes are supposed to have heavy flywheels. Gas Gas now do bolt on additional weights for the Pro so if they do one for the 02 Pro I would buy one if I were you as that is the easiest way to knock the edge of a jerky and over-responsive bottom end without having any detrimental affect on the bikes ability to still respond when the throttle is snapped open. The extra weight will kill the lumpiness and the bike can virtually be ridden old-fashioned style. I speak from the experience of riding a friends 05 250 Pro before and after the weight was added. Before it was just as you describe and horrible to ride. After, I could ride it the same as my Ossa, clutch out.

[gasgas]

Thanks everyone, for thinking with me. Great responses. And yes, i was speaking in general about the flywheelweight. As i stated it is not a big deal, and reading yr responses about the nowadays and older 2strokes i am glad i asked this question. I am again wisened up a little. Ahh internet, how we ever did without.