CruxGNZ

Yes, they are. Front was drilled 2.05mm and the rear was drilled 2.10mm. I have fantastic top end. I believe my jetting (main jets anyway) is spot on, because my Flo-Commander is at 1 turn out.

All the information I read stated that Keihn jets were measured in millimeters. So, my front main jet is a 205 and the rear is 210. Where did you read otherwise?

I tried turning out my fuel screws last night and throttle response got better. I went all the way to 4 turns out and it kept getting better. Going to swap to larger pilots. But, now that is something that is bothering me. Because last year, when I was tuning the bike, it felt like the carbs were getting better as I kept going down sizes on the pilots. I am just going to chalk this up to me not knowing as much as I do now about tuning these carbs.

I have NO IDEA how many times I have taken the carbs off or have changed jets. Oh! Speaking of which, I got a Pit Posse Angle Driver and it works awesome! I got it brand new for $20 on eBay. It is surprisingly made very well. I can now change jets very easily through the frame without removing my GPR V4 stabilizer, lifting or removing the tank, airbox, etc. Getting the bottom of the float bowls off and changing jets are a piece of cake. However, putting things back in place took a little prop rod to hold the bottom of the float bowl in place, while you get one screw in. I needed to do it this way, simply because there isn't enough room to get a hand in there while the tool is in there as well. It is still much faster than taking everything apart.

8541Hawk

Drilling mains could add extra issues that you might not intend.

I say this as jets do not have a straight through hole from the factory (doesn't matter which factory, they all do it) but instead have a venturi shape.

So when you start drilling and now have a straight hole, it is hard to know what you have done to the flow rate.

CruxGNZ

I saw this under a magnifying glass. I was worried, but I can always go back to stock.

I would love to install factory jets, but nobody makes them as big as we are using. Unless you possibly know of any companies that make 205 & 210 main jets for our carbs? Anything smaller and it runs very lean, well, my bike anyways.

NZSpokes

Well if the size works, it works. I concur on that size being very good. just need to sort the part throttle. I suspect mine will improve with the bigger idles. Hope to pull the tank today to replace the petcock.

Spent 5 hours yesterday refitting insulation under the house on my back. Walking around like Im 110 years old today. Damn dog.

Yeah Ive been doing the through the frame thing for a while. I moved the bottle.

Yeah shame we cant get the bigger mains so we have to drill.

8541Hawk

Didn't realize you guys were running that big......lol
As for sourcing jets, have you tried Sudco? If they don;t have it, it doesn't exist....lol

8541Hawk

Another option that you guys might want to explore is to plug the air bleed.

Then drop the mains around 10 - 14 sizes and see how things work.

This is what HRC did when running ram air and might be the reason they went with it as it does work well up top but bottom end ride-ability suffers.

CruxGNZ

Just checked Sudco and they only have up to 200. It was worth checking though. Thanks.

8541Hawk, would you be able to give any insight on what could be causing our part throttle hesitation? At 50%-75% throttle during a gear change, I get a hesitation. Like it's not getting enough fuel. However, full throttle runs are fantastic! No hesitation at all.

I swapped out my DJ short springs and put my stock springs back in and it seems to have fixed the issue, but I was only able to ride the bike for a few miles, so not sure if it is really fixed actually. Could this possibly be a slide issue? I have Dr. Honda veloctiy stacks and if it matters Factory Pro needles with one slide hole.

8541Hawk

Sounds like a slide speed issue. Now whether they are going too fast or too slow is unknown but sounds like maybe too fast as the heavier springs have helped you out.

CruxGNZ

Thank you for your help.

So, if the slides are in deed opening to fast, a smaller than stock hole would help, correct?

NZSpokes

Mine is like a lean out, she cuts right out then comes on strong with more throttle. I do have both holes in the slide open.

Will test ride it as it is. See if the bigger idles help. If not then I will block one slide hole. Worth a crack.

But like the idea of blocking the air jet. I have though that more than once.

CruxGNZ

Exactly what is happening with mine, but I have one hole in the slide. Perhaps a smaller than stock hole (just one hole) will help?

NZSpokes

Funny thing was when I went leaner on mains it got a lot worse. It feels lean but what you have done is made it leaner?

Stephan

I bought jets here last time, they have required sizes. But shipping costs is higher.

KEIHIN : Main Jet CVK/Main Air Jet FCR [313-100]

CruxGNZ

Stephan, thank you for the link! They actually have jets listed that are over 200. They have 210, 220, and even 230. However, they do not show that they are in stock, so lets see what happens when I order two of the 210 main jets. The jets are $4.03 and shipping is $10.07! Well, it is coming from Japan.

I wish I had known they had these jet sizes a month ago. A member here was buying some parts from Webike and qualified for free shipping. He invited us to get in on his order to take advantage of the free shipping.

VTR1000F

There are additional sizes over 200 further down the list.

CruxGNZ

I never went leaner on the mains. I was at 198F & 200R and it was lean up top, so that's why I drilled the mains to the equivalent of 205F & 210R. It feels great now. I'm at one turn out on the Flo-Commander, so I think this is it for the mains.

CruxGNZ

Top of the list is main jets and the bottom of the list looks like those might be main air jets for FCR carbs. This is just an assumption though.

I think I'll hold off buying those 210 mains. It would be great if those are in fact the correct mains, then I would buy 202-212 mains. Along with the Flo-Commander, this would help tuning a lot.

Stephan

my understanding is all jets are the same, only size differ :-)

edit: I bought sizes not marked as "in stock" without problem. But generally if they have item which cannot be provided in weeks, they refund money back without problem. I was pretty satisfied with japan.webike service.

bewsted

So is it safe to say that I need to get my setup checked out. After removing PAIRS and adding crankcase breathers and a K&N i definitely picked up some juice up top but am now struck with the part throttle burps....It almost sounds as though the slides close off randomly.

NZSpokes

Bigger idles have helped. Playing with fuel screw to improve it further.

CruxGNZ

Confused about what the hell is wrong with my tuning, I decided to try something and bog the hell out of the engine. 6th gear at 35mph and I floored it. I was able to hear each intake and exhaust pulse, but the front and rear cylinder weren't equal. You could not only hear it, but feel that each cylinder wasn't equal. This confused me, because I have sync'd the carbs each time that I needed to remove the carbs for any work that needed to be done.

I went home and sync'd my carbs again. This time, I checked out each vacuum line on the bike and made sure there were no cracks (everything was replaced with new lines a couple years ago when I built the bike). Turns out there wasn't anything wrong with my bike, but with the damn Two Bottle carb sync device! One hose had a very small crack in it. How this happened, I have no clue. I made the Two Bottle carb sync device two years ago and all the parts were brand new.

I replaced the lines and sync'd the carbs again. They were WAY off. I took 'er for a ride, and it is SO much better! No more hessitation. This tuning issue was just because the carbs weren't sync'd? Damnit!

On the ride home, I turned the fuel screws out some (now at 3.5F & 4R) and it felt a lot better, so I am installing 48 pilots tonight.

bewsted

I really need to get intune with all this carb tuning LMAO!

CruxGNZ

Have you done the FIL mod as well? Or are you just talking about carb tuning in general?

bewsted

Carb tuning in general. I'm entirely too used to tuning via PC on cars LOL!

Spoot