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What did you do to your Beta today ?

offworlder

By offworlder,
in Beta Motorcycles

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Oval bored my 39 mm FCR to 41 mm using a die grinder and finished off with 80 grit flapper wheel.Had to go up one on the pilot and two notches richer on the needle. Feels pretty good for for a base setting and sounds wicked with a sx silencer.

I have bored carbs before though I can't say I ever used a die grinder. You're a lot braver then me. I used a mill to do oval and round boring. I have to believe the factory went with the 39 for low end grunt instead of the 41 for more top end.

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tractorbeam30
tractorbeam30

I bought it. 

look-pro-go-slow
look-pro-go-slow

Well, not today, but yesterday I got the best finish in my short racing “career”. Smashed the holeshot and placed 3rd in my class. My 2019 Beta200RR was amazing as always.

XRalways
XRalways

Picked it up from the dealer!    

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Odysseus Grand Master

Odysseus

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I have bored carbs before though I can't say I ever used a die grinder. You're a lot braver then me. I used a mill to do oval and round boring. I have to believe the factory went with the 39 for low end grunt instead of the 41 for more top end.

 

 

   I dont see a downside to a 41 on a 498 or 520 series. The limiting  factor for mass airflow  at part throttle is still your right hand whether its 20% opening on a 39mm vs a 15% opening on a 41mm hole, its all the same till  you go wot. Fuel economy I'm not so sure about. Do you still have the capacity to do oval bores?

Edited by widebear
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Rotax Veteran

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   I dont see a downside to a 41 on a 498 or 520 series. The limiting  factor for mass airflow  at part throttle is still your right hand whether its 20% opening on a 39mm vs a 15% opening on a 41mm hole, its all the same till  you go wot. Fuel economy I'm not so sure about. Do you still have the capacity to do oval bores?

I have very limited access right now. The machine shop i use the equipment at has too big of back log at the moment. Usually you would bore them when a larger size carb isn't available. If I can just buy a larger carb, I do. My 52mm carb didn't flow enough so I opened it to 54mm. You will get accelerated wear on the slide though. Mine was for a drag sled that seen about 3 miles of use a year.

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weantright Grand Master

weantright

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I've mic theirs in the past and they are nothing more then off the self jets. Some have extra notches but thats it. The price you pay for their kits equals being raped. It's just convenient for those that don't have the experience or knowledge of carb tuning. An in house CNC would be foolish. Pay a machinist $30.00 a hour to produce $7.00 needles for a very limited run. Motorcycle and car manufactures are nothing more then assemblers. Their suppliers ship the parts and they put them together. They do limited spot welding and all the painting but most is from suppliers. At GM and Dodge if a vehical gets a 1/4 panel dented, the car is crushed and wrote off. Same goes for electrical problems etc.

 

I wasn't talking about the jets just the needles and they are their own tapers. I also didn't say Beta would do production runs with their CNC shop. The CNC shop would create a custom needle spec that's it. $30 is nothing for R & D.

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ballisticexchris Grand Master

ballisticexchris

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   I dont see a downside to a 41 on a 498 or 520 series. The limiting  factor for mass airflow  at part throttle is still your right hand whether its 20% opening on a 39mm vs a 15% opening on a 41mm hole, its all the same till  you go wot. Fuel economy I'm not so sure about. Do you still have the capacity to do oval bores?

 

 

I see a downside to the larger carb. Throttle response at lower rpm. While the larger throttle body makes sense if you are an "A" rider or drag race, for guys like me it makes no sense at all. I'm no engineer but I know the effects of larger carbs. An example would be my 300. It comes stock with a 36mm bore PWK. I have a 38 PWM setting on my shelf right now gathering dust. It's good for nothing more than pinning the throttle with a 10 paddle in the dunes or desert racing on the fast novice "easy loop" through sand washes. Everywhere else it sucks. Almost unridable when doing walking pace single track. I tried every jet, needle, and slide you can think of and could never get it running right at low throttle settings.

 

OTOH, my 36mm PWK with the "Powerwing" installed, runs crisp and clean everywhere except WFO. A fair tradeoff for the type of riding I do. IMO, the reason the bike runs so much better at low speed throttle settings, is because of the "Powerwing". I broke out the mic, and discovered that the wing actually makes my carb bore 35mm.

 

I have very limited access right now. The machine shop i use the equipment at has too big of back log at the moment. Usually you would bore them when a larger size carb isn't available. If I can just buy a larger carb, I do. My 52mm carb didn't flow enough so I opened it to 54mm. You will get accelerated wear on the slide though. Mine was for a drag sled that seen about 3 miles of use a year.

 

Again, different applications. Large bore for upper RPM running. 

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ballisticexchris Grand Master

ballisticexchris

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Is it me or are you running pink lemonade?? Strawberry milk?? :thinking:

 

BUSTED!! I'm actually  treating my bike to the VP Street Blaze sold here at the pumps. I've been running it the last few months. While it does not add HP, the bike runs cooler, smoother, and "roars" in the sand washes. The top Kriega bag actually has a 6 liter MSR water bladder filled with extra fuel. The way you see it here, I'm good for 200 miles. I'm riding with a guy who will be taking his 300RR. We are 75 miles between fuel stops tomorrow. I'm the pack mule.

 

Here is a picture of the bag just in case someone here wants to try it. Crash tested and very durable. 

 

msr_dromedary.jpg

 

Sold at your local tree hugger store:

 

http://www.rei.com/product/733950/msr-dromedary-bag-6-liter

Edited by ballisticexchris
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BUSTED!! I'm actually  treating my bike to the VP Street Blaze sold here at the pumps. I've been running it the last few months. While it does not add HP, the bike runs cooler, smoother, and "roars" in the sand washes. The top Kriega bag actually has a 6 liter MSR water bladder filled with extra fuel. The way you see it here, I'm good for 200 miles. I'm riding with a guy who will be taking his 300RR. We are 75 miles between fuel stops tomorrow. I'm the pack mule.

 

Here is a picture of the bag just in case someone here wants to try it. Crash tested and very durable. 

 

msr_dromedary.jpg

 

Sold at your local tree hugger store:

 

http://www.rei.com/product/733950/msr-dromedary-bag-6-liter

Running higher octane then required is a waste of money. True, your bike will run cooler and the fuel has a longer shelf life. That's where the benefits end. Your smoothness comes from a slow flame front and slightly less BTU's causing your piston to experience less pressure on it.You will make less HP. A much cheaper way to make it run cooler is up the jet size or mix Toluene in your fuel( 20% max) Either way will result is less HP and cooler temps. Heat makes HP but there's a fine line between running on the edge and smoking a piston. 1320º at 100 mm off the piston squirt is burn down for my sled but I run 1470º for 500 ft and less tracks, anything longer and the piston is an ash tray and the exhaust port is smeared pretty good. If you do experience a gain with higher octane, then something is amiss else where. I would venture in the engine electronics.

 

I wasn't talking about the jets just the needles and they are their own tapers. I also didn't say Beta would do production runs with their CNC shop. The CNC shop would create a custom needle spec that's it. $30 is nothing for R & D.

Needles are jets but most don't think of them that way. Yes, I was talking about the needle when I mentioned the off the self comment. My brothers DRZ with the JD needle mic the same as my stock needle. Only difference was his needle had adjustable clip positions. I accomplished the same thing with shimming the needle with washers. I know all about R &D, I spent 7 years in a leading power sport manufactures race department doing that and wrenching. I'd still be doing it if I wouldn't had got burned out being on the road. I just tinker on my own stuff now and still have my contacts I made in those years. 

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ballisticexchris Grand Master

ballisticexchris

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Running higher octane then required is a waste of money. True, your bike will run cooler and the fuel has a longer shelf life. That's where the benefits end. Your smoothness comes from a slow flame front and slightly less BTU's causing your piston to experience less pressure on it.You will make less HP. A much cheaper way to make it run cooler is up the jet size or mix Toluene in your fuel( 20% max) Either way will result is less HP and cooler temps. Heat makes HP but there's a fine line between running on the edge and smoking a piston. 1320º at 100 mm off the piston squirt is burn down for my sled but I run 1470º for 500 ft and less tracks, anything longer and the piston is an ash tray and the exhaust port is smeared pretty good. If you do experience a gain with higher octane, then something is amiss else where. I would venture in the engine electronics.

 

 

This is the reason I'm apprehensive about posting about race fuel. Everyone has an opinion on it. I come from a simple background and just know what works. I'm not looking for HP. My motor runs better and cooler (temp wise), and the oxygenates (or lack of)  in the fuel add to the performance increase. BTW, I currently work in and have over 10 years in the petroleum industry and will just leave it at that.   

 

If I want HP, I just pour in the U4.4. Less octane but perfect for nosebleed elevations without the need to re-jet.

Race fuels also have a more consistent non seasonal blend and many don't contain alcohol or aren't oxygenate. That's where the benefits end but you know that with all that racing wrenching experience.

 

Now your talking. Consistency is one of the key factors. 

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ballisticexchris Grand Master

ballisticexchris

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A much cheaper way to make it run cooler is up the jet size or mix Toluene in your fuel( 20% max) Either way will result is less HP and cooler temps. Heat makes HP but there's a fine line between running on the edge and smoking a piston. 

 

 

Please sir don't be giving advice for someone to mix paint thinner (toluene) in with the gas. Rotton, rotton advice. I've seen so many damaged motors over the years using that crap. Just like guys that used mothballs back in the 80's for octane booster. How do I know? I'm one of those guys......

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redpillar Experienced

redpillar

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Please sir don't be giving advice for someone to mix paint thinner (toluene) in with the gas. Rotton, rotton advice. I've seen so many damaged motors over the years using that crap. Just like guys that used mothballs back in the 80's for octane booster. How do I know? I'm one of those guys......

I remember that. You are old.

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