Soon to do jets and exhaust

After what turned out to be an unsuccessful trip to try and trade her in on an unreasonably cheap Maxim X, my bike is now back home with me again. I was going to sell her to a friend and buy the X for an even trade. When I got back home (400 miles) the guy with the X called and said he'd sold it out from under me the previous night. He knew I was coming up to get it, but that was all part of the big picture, I guess.

The Seca seemed angered by all this and refused to start once removed from the trailer. I had limited tools and did what I could while there, but decided to just bring her home. At first she didn't have any spark, which has happened before after a drop. I fiddled with the electrical connections and the spark came back. Now it still won't start. Plugs look dry. Now that I've got spark I've got a fuel delivery problem, and the bike started right up to drive it onto the trailer yesterday. It's just mad at me.

Today I ordered all the stuff to do her some justice. I was getting sad at the idea of trading her in anyway. I put pods on two summers ago and never completed the job. I got a Jardine exhaust off of ebay, and continued to order some carb rebuild kits and the dynojet kit. I'll also rebuild the petcock and anything else fuel related and check out the tank.

I just figured I'd post and see what people's thoughts were. I know there are the stock only people, and there are the mod people. Personally, I'm really excited to get started. Boxes should start showing up soon. Oh, and I got a colortune for 39 bucks off of Ebay too! That should help.

I'll try to remember to post pics as I go.

Paco

 

Okay....you got a Jardine off eBay, so why don't you send me oyu old exhaust? LOL

 

Not out of the question after I get the Jardine exhaust on. It's a slip on system though, so all I'll have left if the mufflers. PM me and we can talk about it.

 

I did the exhaust/jet thing on mine. Call me a stock guy i guess. Mac and jet kit was about even to stock power with a bit more on the top end. Kerker was a rush, but couldn't jet the carbs enough with the dynojet kit to suit. Jardine slipons were a dissapointment, more restrictive than stock and a weak sound. Hope you did not get the bullet type slipons. Best for the money is the Jardine canister system. Decent power with the kit, a bit loud but really nice design and sound. Gave great midrange and top end with a small loss of the bottom end. I for whatever reason prefer the stock system, nice looking, great design, mine have been drilled at the collector and at the bottom of the outlets. I am guessing to drain water or condensation out of the pipes. They sound great and with the carbs jetted for the K&N dropin gives good power. If Vance and Hines ever made a pipe again or I could get the jetting perfect with a Kerker it might be better, but mine will stay stock for now. cruzerjd

 

Just checked, hope you can get a better sound out of those pipes than I did. Decent manufacturing but seemed a bit restrictive, and sounded thin. cruzerjd

 

Well, we'll see once they get here. If I don't like them, I can always re-sell them to somebody. Had you done pods as well when you tried them? I don't really dislike the stock system either, but since I did the pods I've been running a little lean so I figured I might as well go the whole route and do the jets and exhaust too. I'll keep you updated as to how they turn out and maybe I'll record a sound clip.

 

Pics of the exhaust installed. I've got the carbs off and waiting for the rebuild components. The petcock is disassembled and I'm thinking my main reason for not starting must be dirty carbs because the tank and petcock are clean. I'll know whenever I tear the carbs down. Hopefully the parts get here soon. It's tough to wait when you've got everything all apart.

 

Success! Sort of.

The jet kit came in today, and as this is the first time I've ever attempted to rebuild any kind of carburetor, I took it nice and slow. It took me most of the day to get the work done and make sure I did it right. There was nothing difficult about it. I'm glad I decided to do it myself.

At around 6, I put the carbs back on the bike and fired it up. It fired up. this is an improvement. Unfortunately, I've got a way rich mixture. Deep black exhaust.

I hooked up my colortune to start adjusting and all I can get is an orange flame no matter how I adjust the mixing screw. I realize this is still too rich, but I adjust them all down as far as they will go and it runs ok. It doesn't like to do anything below 3k, but I decide I just gotta take it for quick ride anyway.

The powerband is all jumpy. Nothing until 3k, pulls very hard until 6, flat spot at 6, 6.5 and up it takes off like a rocket. It was still a fun, if cold, ride.

I guess tomorrow I'll go one size smaller on the main jets. This mixture is too rich even with the screws turned all the way down. The exhaust sounds really good. It's not obnoxiously loud, but it flows more than factory. I could still hear myself thinking inside my helmet, so it did just what I wanted it to do. And it looks pretty sweet, too!

I snapped a few quick pics to show the fruits of the last several days labor. Like I said in the "what did you do to your Yamaha today" thread, I've been polishing like crazy and I tucked the taillight under the rear cowling. Have a look!

 

Idle jets - impact mixture through full operation
Main jets - Wide Open Throttle mixture, and impact mid-range.
Needle jets - mid range only.

Do them in that order, otherwise you'll have to redo work as you make changes up the list.

 

That's a great indicator setup!

 

Thanks. That'll help!

 

Thanks. I looked at your gallery and the original setup on your bike is where I got the idea for the taillight.

 

Ok, so this was my first time doing anything with jets and carbs, so maybe I can be forgiven for admitting this somewhat embarrassing fact. I had switched the pilot jets with my new main jets. Stupid mistake, I know. I remember thinking, "That looks like an awfully big change, and this one has a 40 on it."

After straightening that out I cleaned the mixture screws and pathways because I hadn't done it yesterday and "the carbs aren't clean until you do." This didn't take long and soon I put the carbs back on the bike.

It didn't want to do anything until I cleaned the plugs. They were filthy black from my mistake last night. I cleaned them up and got them looking spiffy and put them back after cranking the engine a few times without them to clear it up in case of flooding.

It took a few tries and finally it caught. Didn't even need starting fluid. It stumbled and sputtered for a while, but then got more even. Then it revved up to 6k and sat there. "Oh yeah," I thought as I remembered turning the idle adjustment way up last night to get it to run. I turned it down to a nice 1200 and it sits there steady as a rock.

I hooked up the colortune (neat!) and got a nice blue flame on all 4 cyls. I wondered, "won't that little plastic viewing tube get soft from the heat?" Yes, yes it does. You don't really need it anyway.

So post idiocy, here is a vid of how she's doing now. It just rained again so I'm not going to take it for a ride right now, but it ran wonderfully on its way back to the shed. You can see a little bit of smoke or steam come out when I rev it hard, but I think that's just because of all the moisture in the pipes. Thanks to everyone for the help and the suggestions!

 

1200 is just a tad high on the idle. If you back it down to spec (1050) you'll probably find it just a tad rich.

 

Good info. First time I've even heard of a colortune. I think I'm going to have to order one. I just got my '81 Maxim to start up today. It probably hasn't been run since 2000 (date of last inspection expiration), so I'm happy it ran at all. I'm reading through the forums now, learning about carburetors, 'cause it runs poorly and I expect I need to rebuild the carbs. As long as I'm in there, I figure I'll be rejetting and changing to intake pods.

 

Thanks, Carl.

I got it out again today as it was sunny and in the high fifties. It had been a little stubborn to start since that first day after the re-rebuild and you were right, it was still a little rich. I cleaned plugs and stuff again, had to get it started with starting fluid, and adjusted with the idle around 1050. Much better. I don't even have to choke it to start when it's cold now, and it's always been a real pain to start when cold, and you could pretty much forget about it if it was below 40 degrees.

So I took it for a good long ride on backroads, highways, and interstate and it performed great. Noticeably more power and no hesitation anywhere in the powerband. Honestly, I don't know how much of this is due to the jets and exhaust, or simply to a thorough cleaning of the carbs. The only place that seemed a little gummy was the hats and diaphragms, but those pilot jets being as dirty as they were couldn't have been helping matters.

So thanks a lot for all the help and I hope this thread can assist others undertaking the same task. I should have taken pics of the carbs when they were off, but there are already lots of good carb walkthrus with pics on the site.

I also cleaned all electrical connections while the carbs and exhaust were off, and hopefully this fixes my problem of occasionally losing the spark and having to play with connections until it comes back. I put them back together with conductive copper anti-seize and everything seems tip-top. I'll be trying out some DirectHits on the bike soon, just to see if they make any difference. I'll resurrect this thread with the results.

Paco