Rejetted and Running

[Mad Dawg]

Heya Guys,

I gotta tell you I am stoked. I am no where's near finishing my project, but me and my buddy rejetted the carbs on my XS650 today and got her running pretty damn sweet. I'm not much of a video person, but I took a video of the first run after we put the carbs back on. It's been 25 years since I rode a motorcycle so for safety reason I had my buddy ride her first to see things checked out. I took her for a ride afterwards, then called it a night. Here's the vid link:

On the tech side I rejetted with 37.5 idle jets and 145 main jets. The idle jet had been 42, but we couldn't find any readable numbers on the main jets. After looking at both through a light it was apparent that we had gone up in size on the main. Wish I could be more help on that one. Anyhow, comments are welcome and appreciated. My buddy who has been riding for years was pretty impressed with her.

I wanted to give all of you guys a huge thank you. I read a LOT of info here and don't believe I would have had an idea of what to do without your help.

Later,
Mark

 

[retiredgentleman]

Looks like you have a real fun bike there

 

[Mad Dawg]

Thanks for the nice comment. I'm really happy, though of course we have some tweaking and a lot of finish work before she's ready. I should be getting my finished seat from my sister-in-law tomorrow. Just so happens she is a fashion designer and has a machine to sew leather. She generally makes leather outfits with it, but I convinced her to sew me a seat cover. Just hope it's done so I can go on a real ride. Gotta wire up the blinkers and horn too still, but it's getting there.

Later,
Mark

 

[Mad Dawg]

Heya Guys,

Just an update. The bike is running great and we have the tank and fender painted flat black.. which is the color it will stay. The seat upholstery is done and I'll be riveting it to the pan tomorrow. We are getting close now and I'm getting really pumped. I love the way this bike runs and sounds. There's updated pics in my album and I added another video to the youtube link.

Later,
Mark

 

[5twins]

Well, I've always said that one man's opinion of a good running bike can vary widely from anothers. This is the perfect case in point. I don't think that bike runs well at all. It appears to nearly stall at the end of the video, indicating the low speed circuit is off. That's not surprising since you REDUCED the pilot jet size. Everybody else goes UP a size or two. It also appears to be running rough at higher RPMs, probably due to the too large 145 main, and maybe coupled with not leaning the needle setting to compensate for that large main. But, hey, as long as you're happy, lol. Just be aware that it probably could be made to run much better than that. And I wouldn't rely too much on what a Harley rider is telling you, jeeze, they fix those things with hammers most of the time.

 

[Mad Dawg]

5twins,

Unfortunately, I have to agree with your opinion. My optimism was based upon how badly the bike was running, before rejetting it. However, I took the bike for it's first extended ride today and it was apparent I needed to do more tweaking to get the jets right. It runs much better than it did, but it does need more work. I'm going to put the original idle jets back in and leave the new main jets and see how she performs then. I'll also see about the needle setting you mentioned. I mentioned in another post that I'm a pretty green mechanic and the main reason I posted the video was to get input, so thanks for that.

I did get the leather upholstered to the seat pan today and I'm satisfied with how it came out. Could have been better, but could've been way worse too.

Once I get her closer to optimum I'll post another vid on how she runs and hopefully get some opinions then.

Later,
Mark

 

[littlebill31]

At least you have it running and riding. And are getting a better understanding of the systems. I know a couple people who have a pile of bike still sitting in their sheds, lol.

 

[5twins]

Yes, now you can "ride and wrench". You didn't give the year of the carb set you're using so better jetting recommendations can't be given. The one or two sizes up on the pilots will pertain to all sets but mains of 145 could be too large for some. '78 and newer sets may be able to use mains that big but anything older probably won't.