I holeshot both motos!

[jaguar]

It’s all in having a well maintained engine, good rear tire (with compound density suited to terrain), and correct sprockets. Last motocross I got off mid-pack both times when I was using 13/47 sprockets and starting in 2nd gear (because 1st gear was just too low). This time I went up to 14/49 and started in 1st gear. Man, what a difference! I’ve never holeshot before. It’s a thrill that’s really unforgettable. I was a bike length in front of everybody (13 enduro bike riders), including Honda XR600’s, a KTM 250, and a hopped up DT200. I lead for half the race both times but the DT200 passed me and held the lead. The rider was the champion of the DT motocross series in another city. He was a better rider than me but my KDX had better acceleration. If I was in better shape I could of won. (good excuse, eh?) The bike handles bumpy stuff at speed much better too with the tie rods increased in length by 3mm. I selected the sprocket change after experimenting with different ones at the other tracks start area which is packed hard dirt. (This track had been raked after the last drizzle) Most practice starts with the 14/49 resulted in a slight wheelie (sign of traction) whereas no wheelie was had with the 13/47 sprockets. Here’s a picture of me (#24) leaving them all in my dust:

 

[G. Gearloose]

Good show, Jag!

 

[MX175]

When I was racing a Penton 175 in the mid and late 70's I was able to get the hole shot by starting in second gear. I'd often have a length or two by the first turn. Too bad I didn't have any other skills and struggled to stay in the middle of the pack. Those races were in Byron, Il and they had a 175 class. The only modification was a change to a Mikuni carb.

 

[jaguar]

What's amazing here is that my model only has a 28mm carb.
Yes those old Pentons did have a very low first gear. I had a Penton 125 as my first bike.
Here's a pic with better resolution:

 

[FLBob]

I frequently get the holeshot -12/17 second gear- get passed real soon -sometimes before the first turn if it's very far down the track- by the time I hit 4th gear someone's caught me -I think it's because my 220 starts so easy - when I don't get the holeshot it's usually some guy with the button.

I went to the 12, and stay out of first gear as much as I can, to help with control in the tight stuff.

I'm going to 13/50 for the new season - will the stock 108 link be OK or will I need something longer?

Where to order the chain & sprockets?

Thanks

 

[jaguar]

That's really geared low for motocross. You probably get passed so quickly because you're wasting too much time shifting. Go up in your gearing, use 1st gear to start, and learn how to slip the clutch in hairpin turns.
I like to buy from www.mxsouth.com

 

[JasonWho]

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[marksharp]

I don't think 108 link chain will fit the 13/50 combo- I had to get a 110 link. Love the setup though- good all around gearing.

 

[jaguar]

I think he was referring to the fact that the four stroke MXers have twice the displacement and therefore are better out of the start gate. There wasn't any such animal in my class. Those bikes are just so expensive.

 

[FLBob]

Yeah, Hare scrambles, dead engine start-sorry I wasn't clear. With the 12t in first, I would frequently end up in the puckerbrush from a little too much throttle in the tight stuff. Gotta love that low end torque on the 220!

 

[Jackpiner57]

MX175, I miss my 1972 Penton 175 Jackpiner! It hauled ass!