Questions about jets and excess oil...

MBellRacing · Post by **MBellRacing** » Sun Apr 03, 2011 6:27 pm

PISTON PORT!!! So badass!... sorry about the motor... that's what you get when you buy a strung out street bike!!!

brewsky · Post by **brewsky** » Sun Apr 03, 2011 7:36 pm

Jensen,
The KR is NICE.

I have a friend with an RS250 Aprillia that Dynoed at 60 RWHP..it's not much on the low end but when it Hits...It HITS!

Our shop sold Yamaha Banshee quads (till the quit making them) and they had basically the RD350 motor. Most returned to the shop wrecked!

I have a CB750K with a pumper carb (one carb pump feeds all 4), and it still does not allow instant WOT without some hesitation.....kind of like the old 4 barrel carbs on cars.

teazer · Post by **teazer** » Mon Apr 04, 2011 12:48 am

This is an interesting thread.

RD400 C-E were the same as the rest of the world except they did not get the electronic ignition on the E model. F model (Daytona) US model was very different to try to cut emissions.

My RZ350 runs the same jest at 30F as I run at the race track at 90F ambient. I'm sure it would be slightly better with one size smaller main jets in the summer, but it runs fine.

60HP is a good number from a stock Aprilia RS250, but there's more to be had. Our regularly topped 65 and was a joy to ride. Smooth as silk. It's all in the fine tuning and especially the exhaust power valves. Change that P/V timing and see the effect on the power curve. I only raced them a couple of times, I built them for a guy that raced way faster than I'll ever go.

KR1 was always a little fragile though, but so sharp looking.

You can bang the throttle open on a slide type carb, but only above a reasonable speed. When we run our bikes on the dyno, the operator gets them to about 3k and opens the throttle pretty fast. Try the same thing on the street at idle and it will more or less die.

The RZ does the same thing below say 6,000 - it just make a moaning sound as it slows down if the throttle is banged open. And above that speed in first or second the front wheel comes straight up. So we learn to be smooth and to open the throttle only as much as the motor can use. Less stress and optimal acceleration.

MBellRacing · Post by **MBellRacing** » Mon Apr 04, 2011 1:16 am

Yeah, above 3000rpm my motor sings with any throttle input. Still a hair rich, made obvious by how much better it runs on a cold night than on an 80F day like today and yesterday. Hopefully getting some 135 jets tomorrow to try it out.

Race next weekend that I'm leaving for on Tuesday, so no riding and no updates till next Monday at least. Good news is that I'm heading to Barber Motorsport Park which has the world's largest private collection of motorcycles. If I have time to stop by the museum I'll take some shots!!!

brewsky · Post by **brewsky** » Mon Apr 04, 2011 4:36 am

teazer wrote:This is an interesting thread.

RD400 C-E were the same as the rest of the world except they did not get the electronic ignition on the E model. F model (Daytona) US model was very different to try to cut emissions.

My RZ350 runs the same jest at 30F as I run at the race track at 90F ambient. I'm sure it would be slightly better with one size smaller main jets in the summer, but it runs fine.

60HP is a good number from a stock Aprilia RS250, but there's more to be had. Our regularly topped 65 and was a joy to ride. Smooth as silk. It's all in the fine tuning and especially the exhaust power valves. Change that P/V timing and see the effect on the power curve. I only raced them a couple of times, I built them for a guy that raced way faster than I'll ever go.

KR1 was always a little fragile though, but so sharp looking.

You can bang the throttle open on a slide type carb, but only above a reasonable speed. When we run our bikes on the dyno, the operator gets them to about 3k and opens the throttle pretty fast. Try the same thing on the street at idle and it will more or less die.

The RZ does the same thing below say 6,000 - it just make a moaning sound as it slows down if the throttle is banged open. And above that speed in first or second the front wheel comes straight up. So we learn to be smooth and to open the throttle only as much as the motor can use. Less stress and optimal acceleration.

Teazer,
The Aprillia was not stock, but is "street legal".
It is an imported version, but the guy who imported it knew someone at the DMV who performed some hocus pocus and got a registration card.

We actually sold a new KTM 300XC 2 stroke, and the DMV actually sent the owner the license forms by mistake in the mail. Since KTM MSO's don't differentiate whether they are off road or not, the clerk didn't know the difference, sent the registration fees in with the title application, and presto!

Snakeoil · Post by **Snakeoil** » Mon Apr 04, 2011 9:30 am

A Honda dealer in NY told me that if you find a way to title a bike sold as strictly a off-road machine, there is a $2000 fine if you get caught. I was talking to him about making a CR250F street legal so I could ride it to trails instead of trailer it.

regards,
Rob

MBellRacing · Post by **MBellRacing** » Tue Apr 05, 2011 1:33 pm

Anybody have any stock jet needles they can sell me? I only have the aftermarket ones and don't trust them with the Keihin main jets. I'd buy them from Ohio Cycle but they are stuck in the bronze age (pun) and only take money orders. Seriously? How long has it been since the credit card has been invented?