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Discussion Starter #1
Yesterday I fired up the 175 with the 24mm Keihins and WOW, what a difference. My driveway is too short to ride it on and the hay field was pretty wet so my testing consisted of calling my buddy Joe so he could hear it run over the phone.
Hawk school tomorrow will be a good shakeout.
Right now I have the 100 main jets and needles 2nd clip up from the bottom. Didn't get the airscrew adjusted at all- just 1 turn out from the bottom.
Scott/JohnnyB what are you guys running?

bfd
 

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I found the 102 jets from California, but right now the stock 120s are in. Needle is all the way down. But this is all without testing the bike on any length of track,as you say, just the driveway. With my new exhaust, there is an amazing difference.

I'll be running the SR500 at the track for the morning "practice" (more on that later) and then when it opens up in the afternoon, I'll get the 175 out and we can have some fun. Let's have a drag down the straight. I dont have JB's carbs yet, but I'm 99% sure the thing is going good.

I don't want to pooch the 175 in the am. Plus I have one or two small things to take care of onit, ie scrubbing the new tires etc.

Look forward to seeing you. We should get there by 8:30

s
 

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Discussion Starter #3
Scott
Looking forward to it!
The Dennis Kirk catalogue has a full size run of these jets so I have a few different ones to try. The new Dunlops need to be scuffed in and I hope to have fine German twin to (gently) break in for the morning session.
Hope I can sleep tonight!
bfd
 

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Bill/Scott,

You'll find the bike really comes alive at about 7,000- 7,500 rpm. Also become very easy to get the front end up on starts. Sometimes during the first to second gear change too.

I always start with 100 mains and needle in the center. Sometimes you have to raise the needle a notch to get rid of a dead spot right around 7,000. 120 main jet is going to be way rich. The bike will tolerate a way rich condition easily...so don't let it fool you into thinking it's running the best...dyno tests show the power starts dropping off real quick when it's too rich but it will often sound/feel fine.

That said...I've never run one with OEM 120 mains....you never know how they flow compared to new/aftermarket 100 mains...only way to know for sure is to do some plug runs.
JohnnyB
 

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will do. Is Hiroshi's bike going to be there?

It took me a while, but it's "stanchion"

s
 

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Hiroshi's bike should be there along with Hiroshi.

I expect you guys to help him with any tuning changes should the bike need them. It looked a bit rich to me when I delivered it...better rich for breakin than lean.
You guys know these bikes so keep an eye on his for any of the typical problems.

He's got the PE24's with 102 mains and middle position on the needle. About 45 degrees advance, 15/38 gearing. Check out the belly pan if you get a chance.
JohnnyB
 

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45 degrees??!?!?!?! Wow. I got mine at 40, and haven't gone past that.

s
 

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Scott,
All the dyno work I've done has shown 45 to 50 degrees. 50 is good for peak hp but hurts you in mid range..45 to 47 works good on my bikes.
JohnnyB
 

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Discussion Starter #9
JohnnyB/Evil
I started off the 1st session with the 100 mains and it ran great. Switched to 102.5 and it wouldn't pull and lost about 2k on the tach. Put the 100s back in and ran great the rest of the day. I could even stay with slower CB350s.
Those Dunlops are the nuts.

bfd
 

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Bill, can you give me the page or no. of those filters (air) I went to Dennis Kirk and couldn't find them , actually, I didn't want to spend 20 minutes looking for em if you have the info.

s
 

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Discussion Starter #11
Scott
I'll look them up tonight.

Fun riding with you even though it was short
bfd
 

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If you guys are talking K&N filters I found this place called Martel Racing...they basically drop ship from K&N, you can order any filter that K&N carries. That's where I got the nice tapered filters for Hiroshi's bike and some for Mary's old school Keihins.
Might be more expensive the Kirk though...Martel seems to get MSRP for them.
JohnnyB
 

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For what it's worth...when my son and I were looking for a paper element (K&N style) filter for his S90, we found a really cool looking one at the local speed shop. It's actually a Moroso crankcase breather for a stock car V8...about the right size and shape for his bike, don't know if you'd have frame clearance issues on a twin though.


FR
 

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Discussion Starter #15
FR
I put these on because the angle of the carbs made the round straight ones hang out where my knees hit them.
Good tip on the Moroso's though.
bfd
 

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hey BFD, Thanks for the link to the BMW site. COOL.

Anyway, i got the air filters this morning, they fit, but I probably would have gone up a size, as they are pretty tight.

Did you apply the oil that's enclosed?
scott
 

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Scott,
Don't use the oil, it will restrict air flow.
I basically just use them to keep sand and debri out of the carb. The chances of a race engine lasting long enough for super fine particles to wear it out is pretty much nil.
I also like filters because they create a nice stable dead air space outside the carb inlet...much better than a buffeting wind on the straight at 80 mph.
JohnnyB
 

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Discussion Starter #18
Scott
I used the oil but only one little thingey for both filters. On the advice offered by people here though I am leaving the ones on other bikes alone and not re-oiling them.
bfd
 
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