new GS racer

[Rob S.]

Makes sense

Starting to make sense. I do very little leaning, as I'm just getting back on after a 24-year hiatus.

But I do love taking the heel of my boot and kicking it into first. Damn! I rode four days ago (NYC), and I'm jonesing for more.

1100EZ Vance & Hines, K&N

[GregT]

Impressive - but I'd point out your ankle is one down, three up from the midline...

All your points are valid but it's still down to personal preference really.

[gs58]

P.S. I prefer because GP for two reasons:

1. it's easier for me to get positive gear engagement with a push down, than a pull up. At the track, when a bad upshift can cost you a race, that's important.
2. it's easier for me to upshift when you're heeled over in a corner (and can't get your foot underneath the shifter if you're not running GP). This doesn't happen often but when it does it's nice to be able to upshift at a large lean. (Like GregT noted, this is less an issue nowadays.)

But at the end of the day yes, it's personal preference, whatever you're comfortable with is the way to go. I still run standard shift on my street bikes.

I have considered using the GP pattern but have seen several examples of bent valves due to over revving when natural instinct takes over. You do not want to be shifting from third to second when you are look for fourth and are hard on the gas. There are so few corners where it is an advantage (especially with the GS spread of power) that the risk/reward ratio does not warrant it (for me).

[CivilRock]

Sorry for the hijack Patrick.

If anyone wants to continue discussions about GO Shift, I urge you to go to the thread I started last summer on the subject, and do post your solutions there. This thread is about a sweet GS road racer. http://www.thegsresources.com/_forum...d.php?t=212785

[patrino]

Got the seat finished and put my numbers on.





Had hoped to make it out to the dragstrip last saturday for shakedowns but they canceled due to rain. I have plans to make it up this Wednesday, the weather is supposed to be better.

In the meanwhile I ran the bike around the block. The brakes are TERRIBLE - very wooden. I think it's a master-to-slave cylinder mismatch. I'm trying to track down the piston sizes of the calipers, but a review of the m/c ratio chart available at Vintage Brake makes me think the master cylinder the bike came with (3/4" / 19mm) is way too big.

I was all set to head down into the basement to find an old Brembo m/c I have (14mm or so) when some internet research made me realize the m/c that's on there is an AP Racing adjustable. It looks like I can adjust the lever down to an effective 16mm bore size. Next time I'm down at the shop I'll give it a whirl. If it improves but still isn't good enough I'll have to fit a new m/c with a smaller bore.

In the meanwhile, if anyone has an EX500 shop manual in their garage, I'd appreciate the caliper piston diameters, please!

[CivilRock]

** GP shift**

Patrick. If it's dry Wednesday night, I'll totally race you at the PIR street rips. Shoot me an email if you're going.

I need to fabricate a chain guard for my bike, and it looks like you might too. Seems like a silly requirement, but they stopped me last time. That my my helmet wasn't SNELL 2010. (It was Snell 2005). They gave me a warning on the chainguard, but I had to borrow a helmet to pass tech.

Kevin.

[CivilRock]

Wednesday looks like the only dry day this week.
Kevin

[GregT]

Ex500 is 14mm, hook out that old Brembo....

[patrino]

Located a couple used master cylinders, going to do some experimentation over the weekend.

Shoot. My helmet is 2010 Snell but no chainguard. I'll see if I can kluge something together for tomorrow.

And yes, GP shift.

[patrino]

I swapped out a 14mm master cylinder, it was a big improvement over the AP Racing one, but it's still not as good as I'd like. I roughed out the numbers yesterday, I'm at a ~18:1 slave/master ratio. I've got a line on a 12mm m/c, I think that'll do the trick.

That said, I could live with the 14mm if I had to.

Drag races were canceled last night, so I just ran it around the shop a few times. Still no leaks, which is good. The CRs pop a bit at ~1/8-1/4 throttle, I'll futz with that this weekend and try to get it tuned out.

[gs58]

Your bike is looking great Patrino. I look forward to seeing some results. When determining a master cylinder it's not just the size of the master cylinder that counts - the location of the pivot point of the brake lever can also change the feeling and effectiveness of your brakes. Not all 14mm (or 12) master cylinders will be the same.

[GregT]

Your bike is looking great Patrino. I look forward to seeing some results. When determining a master cylinder it's not just the size of the master cylinder that counts - the location of the pivot point of the brake lever can also change the feeling and effectiveness of your brakes. Not all 14mm (or 12) master cylinders will be the same.

Very true...believe it or not, the best we've found is actually a GS450 14mm master. Better leverage than anything else we've tried.

[patrino]

Found an inexpensive 1/2" m/c from a friend who's a bike breaker, and put it on last night. It's a bit too far in the other direction: much more lever travel than I'd like.

GS85 and GregT, thanks for the tips. Pivot length for both the 1/2" and 14mm m/cs were about the same, so most of the braking feel difference seems to be attributable to the bore size difference. I'll probably run the 14mm one for the first weekend, but I'd still like to try a 15mm or 5/8" unit to see how they feel.

Anyway, working through all these master cylinder swaps and experimenting now gives me a much clearer picture on what piston / master cylinder ratios really mean "at the lever". That alone was worth it. I'm only down a couple pints of DOT 4 and $20 (and a six-pack) for the 1/2" master cylinder!

[patrino]

Traded my buddy the 1/2" m/c for a 5/8" (16mm) master cylinder, that's the ticket for me!

All set to go now, bike is plugged into the battery charger, ready to load up on Thursday night.

[MK3Brent]

Good luck. Keep it stick side down.