My 2007 Kinroad XT200GY Runmaster

[Weldangrind]

Originally Posted by ripcuda

Next up after all that... I would like to find a firmer rear shock. I'm finding my bike bounces too much after a bump and it sags a good bit under my heft. There is sadly no preload or any adjustments on the stocker. Guess I could try to shim the spring for preload. Plus being direct to swingarm mounted shock... it's pretty short overall and not much room surrounding it. Joy. Perhaps some other China bikes have a stiffer shock that could work... but how to find them...

Cheers!

I have a Kawasaki ZX-6 shock that might do the trick; it needs a good home. Do you care to remove your shock and measure it?

[Weldangrind]

Originally Posted by jct842

Some say a drilled out jet will actually work better as the rougher surface gets the fuel swirling and more inclined to go to vapor. If you do have a jet working right I would not change it no matter what.....when it is working right how much better can it work?

That makes good sense. I drill out jets quite often, but it never occurred to me that they might be superior to factory jets.

[ripcuda]

I've read various opinions one way and the other regarding drilled out jets and their flow characteristics. I've looked at new ones up close under a magnifying glass and then the ones I've drilled. The chamfer on the orifice is smoother and better sloped on new ones. When you over-drill a jet... you remove most of that. I think flow through the jet... smoother, less restricted... is more important than atomization (swirling/dispersing). And any rough surface, seems to me, to inhibit this flow more than a smoother one. So... I'm in the manufactured jets flow better than drilled jets camp. But, honestly, with such small displacement engines and jets... I doubt the differences are really measurable.

Cheers!

[ripcuda]

Originally Posted by Weldangrind

I have a Kawasaki ZX-6 shock that might do the trick; it needs a good home. Do you care to remove your shock and measure it?

Very kind of you to offer for consideration.

Here is the dimensions of my stock shock:

Bolt center -to- bolt center: ~9 7/8" = ~250mm
Bolt holes (both): ~ 0.45" = ~11.4mm
Spring height: 6" = ~150mm
Spring diameter: 2.66" = ~67.5mm
Perch/mount width (both): 1.3" = ~33mm

It's a pretty short overall length shock. And I don't have much room top or bottom to handle reservoirs and whatnot... so alot of the R6 and street bike shocks probably won't work.





Cheers!

[ripcuda]

Originally Posted by ripcuda

So I found my next smallest drill bit above my numbered set (maxes at #61) and it turned out to be 0.0465" (#56).. or ~1.18mm (#118 jet). I hear you... don't do it... baby steps! haha. So I drilled out my old main jet I've already messed with (keeping my current good #110) and put it in. While in there... which is an annoying process to unbolt, unclamp, and rotate the carb to gain bowl access... I figured lets throw back in the ~#45 pilot jet too for good measure. I hear you... no... one change at a time! haha. So changed out my 40/110 to a 45/118. It better be rich enough now!

Got to finally ride the bike after the above carb changes today. I didn't even get 100 yards down the road when I knew it was pig rich. Stumbling, blubbering... wouldn't rev up quick. Lots of stumbing at revs. It was unrideable. Made it a mile down the road and turned around. As I was reving out an upper gear... it was sputtering bad... which reminded me of that same think that happened at the last tune (40/110) a few times as I winded out top gear. That got me to thinking... perhaps I wasn't lean, but a tad rich up top.

So back into the shop. I've got this carb unbolt and rotate down pat now. So 45/118 is pig rich... back to my known good 40/110 jets. And this time... I'm going to lower the needle one notch. The needle has been in full raised (lowest clip) position this whole time. So I dropped it down by raising the clip one slot (one below middle). And back in went the good #40 pilot and #110 main. After dinner... another ride.

Ah... running great! Even better than before. No stumbles, no popping decel, no loading up at extended coasting/idle, no more top speed run stumbles, no bogging on sudden throttle grabs. It feels better than it ever has. Plug looks good. I think this is it!

PZ30 carb: #110 main, #40 pilot, 1-2/3 turns out on the mixture screw, Needle clip one below middle.

Can't wait for my sprocket... and tiny tach.

Happy Memorial Day!

[jct842]

And when they are right you just can't make it righter!

[SpudRider]

Good for you, 'cuda.

[Weldangrind]

Excellent progress on jetting! Jetting tenacity really pays off.

[Weldangrind]

Originally Posted by ripcuda

Very kind of you to offer for consideration.

Here is the dimensions of my stock shock:

Bolt center -to- bolt center: ~9 7/8" = ~250mm
Bolt holes (both): ~ 0.45" = ~11.4mm
Spring height: 6" = ~150mm
Spring diameter: 2.66" = ~67.5mm
Perch/mount width (both): 1.3" = ~33mm

It's a pretty short overall length shock. And I don't have much room top or bottom to handle reservoirs and whatnot... so alot of the R6 and street bike shocks probably won't work.

The shock I have could perhaps be made to work, but not without some mods.

Since you speak Metric, I'll use that system.

Bottom bolt center to base of top stud - 370mm
Bottom bolt center to top hole center - 340mm
Spring height - 180mm
Bottom bolt hole diameter - 10mm
Top bolt diameter - 10mm
Spring diameter - 83mm
Bottom width inside - 30mm
Bottom width outside - 44mm
Top width at mount - 28mm
Top stud diameter - 16mm

[ripcuda]

Thanks for the details Weld! Not sure that puppy will work. The reservoir would not fit in my current space... plus it's really long.

I've found these universal shocks on ebay... 250-260mm tall... with some good spring rates. I think one of these could work with a little mounting point tweaking.
http://www.ebay.com/itm/171802639687...%3AMEBIDX%3AIT

http://www.ebay.com/itm/181559616937...%3AMEBIDX%3AIT

Got my 17T sprocket yesterday... hope to install it this afternoon and take it for a blitz.

Cheers!

[Weldangrind]

Yeah, I might install that shock in a dirt bike I'm building. I need to weld in the bridge for the monoshock anyway, so I should be able to raise it accordingly.

That red anodized shock is a fair price, but Humanbeing might be able to point to a better shock that is cheaper.

[ripcuda]

More progress... so I worked on installing my 17T front sprocket. It did not slide on perfectly at first. The casting was not deburred at all... so I had to spend some time doing that. Then I had some fitment issues with the splines on the sprocket. More rough castings that I had to file... each groove and spline. But it does fit and should work fine now.



This is the largest sprocket that can fit... for sure. Very close fit with the chain installed. Here is an overlay of the 15T sprocket on top the 17T sprocket.



As expected, my 124 link chain was a few links short. So I've begun fitting my RK 130 link chain. Will need to remove a few links... but first wanted to position the rear wheel full forward.

While I had the tire off... I measured the rear sprocket. Mine is a 46T for a 428 chain. It measures a hair over 3.5 inches... so probably 90mm. Also held on with a large cir-clip you can see in the pic.



Also of note... the wheel bearings for my rear wheel are 6202 series... one on each side.

Lastly... a shot of my direct swingarm mounted rear shock. It is slightly offset to the right to make room for the airbox and such... I presume.




Hope to finish up with the chain tonight and give it a whirl.

Cheers!

[SpudRider]

You are making good progress. Thanks for posting the update with the excellent photographs.

[ripcuda]

Wrapped up the sprocket swap and re-chain this evening. Had to cut 4 links off my new 130 link RK chain... so 126 links needed with the 17/46 combo. My original chain was 124 links for the 15/46 combo. Set my chain slack for my weight... and it all rolls nicely.

I also put on my tiny tach... a fleabay hour/tach meter... the small waterproof cheap one. It works off a wire wrapped around my spark plug wire. Seems to work great... reads RPMs as soon as the bike is running. But now that I see RPMs... they sure look low to me. My bike is comfortably idling at 650-700 rpms. Does that sound right? And when I took it for a ride... I did a top gear pull... and only saw 3800-ish? That just seems low. Could it be half the true rpm? There are no buttons or settings on my cheapo tiny tach.

So I got to take the bike for a short spin this evening. I am very happy with the 17/46 combo. 1st gear is actually usable now... and it "feels" like it's in the right gear when cruising down the road for the given speed. It was about to rain, so on another day I'll get the GPS and check top speed and comfortable cruising speeds.

Next up... front rim wobble and rear shock... eventually.

Cheers!

[Weldangrind]

Originally Posted by ripcuda

More progress... so I worked on installing my 17T front sprocket. It did not slide on perfectly at first. The casting was not deburred at all... so I had to spend some time doing that. Then I had some fitment issues with the splines on the sprocket. More rough castings that I had to file... each groove and spline. But it does fit and should work fine now.

I'm surprised to hear that. I've never had to deburr a sprocket or countershaft, Chinese or otherwise.

Originally Posted by ripcuda

This is the largest sprocket that can fit... for sure. Very close fit with the chain installed. Here is an overlay of the 15T sprocket on top the 17T sprocket.

So we'd think, but forum member Jibberwobble actually found and fit an 18 tooth in there!

Originally Posted by ripcuda

Lastly... a shot of my direct swingarm mounted rear shock. It is slightly offset to the right to make room for the airbox and such... I presume.

Interesting that it is mounted to the swingarm, and not a link. I agree that it's likely offset to clear the airbox.