IN NEED OF MAJOR HELP!!! 81 seca 750 needs to start running

ok i have a 81 seca 750. it did not run when i got it. so i got a ignitionmoduale and fixed the spark isue and it would run if i spraid gas in by hand. then i cleaned the carbs good and it didnt fix anything. (also i put a straight pipe on it and pod filters since old air box was crushed and old pipe was bent and blockeing anthing from comeing out) i also put my hands over the air intake of the carbs and it would run better. so i thought bigger jets! but ieveryone i got from yahmaha did not work(would not thred in) so i got a dino kit and put the dino kit in the carbs. well now i cant get the bike to start for anything i spry gas in nothing i spray starter fluid(only did once to see if anything sould happen) and nothing. checked spark and its working. i stoped trying and all a suden back fire! so i figured it fluded. but now i am lost and have no idea what to try or do. i am open to all ideas and will keep daily updats for all of you. Thank You!

 

basics first.

1. Spark still good?

2. Float levels set by the wet method?

3. Carbs clean enough to eat off of inside?

4. Enrichment "choke" circuit in the float bowl clean?

5. Pilot mix screws at 2.5 turns up from soft bottom?

6. Fresh plugs?

7. Good gas?

8. Valves clearance checked?

9. Battery good and fully charged?

Answered yes to all those? Compression test and we'll go from there. Pods can alter the tuning process some but if it's not starting there is no tuning process.

 

Start with NEW spark plugs. If those got saturated they will drive you crazy.

Then everything on the above list, in order, no skipping.

 

ok spark was good, what is the float lvl set by wet method?, yes carbs clean enough to eat out of, the choke part what are you talking about?, new plugs and new ultimate gas, valve clearance check how sould i do that and my bike battry whent bad so i tried a full size battry would that hurt anythingjust to start it?

 

Using a car battery could have done damage.

Valve check and adjustment as well as how to "wet-set" floats are covered on this site; look in "FAQ Suggestions" or do a forum search.

There is no "choke" he's referring to the enrichment wells which are actually drillways located in the float bowls.

 

I would suggest backing up. Pull the carbs back off. Return the carbs back to stock set up. Get the stock air box and forget the pods. Take the carbs apart and clean them the way the carb cleaning threads tell you to clean them (there are a couple of good ones on this forum). Put in your location so that if someone is in your area they can offer to swing by and give you a bit of help. The reason I am suggesting that you clean the carbs again even though you said that you already cleaned them is because you just joined this forum in February. It took me three tries to get my carbs clean (that was a month of after work hours). What do you mean that the air box was crushed and what pipe are you talking about? I have an air box but no cover. If your cover is ok you can have this air box if you pay shipping. If you start doing mods (pods and the like) before you even get it running you are inviting disaster in my opinion.

 

well when i got the bike the air box was in little pieces all over so it does not have any parts reusable.. and i did git it to run a little when i just put the bigger jets in and b4 i did the rest of the dino kit. it would not idal but if i held the throtle it would run fine. that could just b adjustment. it still didnt seem to be doing 100% right so i put the new needle and everything else you do with dino kits. thats when i got nothing more.

 

and what could i have mest up with the battery?

 

The car battery could have overloaded circuits, melted wires, fried a TCI, etc.

We can get you running without the air box. It's harder but it does work. You'll have to be the judge of how well it runs and the level of tune you are satisfied with.

Add your bike info to your signature and a gerneral location to your profile, someone maybe near by to help.

Then, get the new plugs as fitz suggested and repsond back to my list 1-9, numbered, do we can keep track. Honest answers or we'll all chase our tails.

This forum can get your bike running. It's done it before and it'll do it again.

 

ok thanks guys when i get home i will try and get some info up for you guys so you know what is the update and i will try to get the stuff tomorrow so i can decide everything thank you guys fordoing this for me and i am located at 45068 just for those who see this b4 i get home and set everything up and i cant stress enough how thankfull i am to have you all help me!!!!

 

Do you even know what size jets were in the kit? Did you possibly mix up the main and pilot jets when you installed them?

You really do need to slow down and back up, and proceed methodically. The first possibly false assumption you made was that the kit is going to provide the correct jetting. You can't just install stuff without even knowing what it is; motorcycle carb tuning isn't "plug-n-play."

 

Umm, what?

I could be crazy here, but I'm pretty sure you can't fry anything by using a bigger battery of the same voltage. 12 volts is 12 volts is 12 volts, be it from a bike battery, a huge Group 31 battery, or 8 AAA batteries hooked up in series. Excess supply can't cause excess demand.

Besides that, higher voltage means lower amperage for the same current draw. Since a bigger battery would have less voltage drop with a load on it, the amperage through the wires would be lower, not higher. If your starter draws 300 watts, it's pulling 30 amps @ 10V, but only 25 amps @ 12V.

 

"It didn't run when you got it!"
So, ...
You have to go to "Basics" on the one hand and, "Experimentation" on the other.

Do a Compression Check and get an idea of what your dealing with.

If the Compression is within Specs, ... then you need to decide what you're going to do regarding: Tuning.

At this writing, there are very few Members who are completely satisfied with how well their Bike is running with aftermarket PODS instead of the Stock Airbox.
I haven't kept track of exactly how many.
Enough to play "Hide-and-go-seek."
Probably not enough to play Softball.

You will spend less time and experience less complications if you acquire a used airbox and restore the Intake to the Factory condition.
With an Engine that is healthy enough to run well; you'll have less to do and fewer complications to overcome to get the Bike Tuned and on-the-road.

http://storage1.colony1.net/2195/Produc ... %20099.jpg

http://www.drumhillcycle.com/index.cfm/ ... /3,3880199

 

Re: IN NEED OF MAJOR HELP!!! 81 seca 750 needs to start runn

well i would rather just get it going with the pods than spend 60 more dollars on an air box.... i am on a strick budget

 

I got a new airbox off eBay for $10 shipped.

You're looking at spending a lot more on carb parts if the "kit" doesn't provide the correct jetting for your modded bike.

 

it only came with main jets and it came with 4 diff sets the 120 124 132 136

 

Re: IN NEED OF MAJOR HELP!!! 81 seca 750 needs to start runn

There's the rub!
You can pop for 60-Bucks and get that Bike hooked-up to where you will only need to adjust your IDLE and SYNC, ...
Or, ...
You can begin what may or may-not be a rather lengthy and aggravating process trying to re-jet and adjust needles to force the bike to run on the Pods.

I look at the numbers and try to draw a conclusion.
Of the 9,000 Members we have in our Forum ...
I'm guessing less than 20 profess to have Bikes running Pods
Of the 20, ... 6 or 8 are Pro-pod advocates and proclaim to have a good running bike.
For this discussion, ... let's say there's 10.
10 out of 9000. (9000 ÷ 10 = 900)
Only 1 in 900 for a satisfaction ratio.
00.01 %
Less than 1 Percent.
Zero point zero one percent.

That leaves you with a 99.9% chance of "No Cigar", my friend.
Them ain't good odds.

You'll hears some say: "It's your bike. Go ahead and try it!"
Which sounds to me, like: "It's your bridge. Go ahead; JUMP!"

 

well another saying money dont grow on trees and cant suck blood outr o turnip

 

lol i basicly am stuck with what i got

 

pods or no pods if it don't run it don't matter.

Let's get back to my first list and get it running. Then you can decide on the pods.

 

firefox is 100% Correct here. You can't "force" current, Voltage is the "push" Current is the rate.

 

I agree, in a perfect circuit. With a short or some other problem it could easily overheat and melt a wire or connector, no?

I think he's got other problems than having used a car battery.

 

If it will run hooked-up to a Car Battery, ... the System needs AMPS.

The Bike battery is too weak to supply enough AMPS.
The SYSTEM may not be generating enough power to sustain the current needed to run the Bike.

Pull the Battery.
Charge it Full.
Bring it to AutoZone and have it "Load Tested" for Cranking AMPS.

Then, when the Bike is running, ... MEASURE the Voltage at the Battery with the Engine making above 2300 rpm's.
The Voltage should be >> 14.2 -to-14.5 (Minimum) to sustain the System while the Bike is running.

 

I'll back you up Rick,
A solid battery is a neccessity. You can use a car battery, it won't hurt a thing but keep in mind that you should NEVER hook up to a running car. Muiltiple main jet numbers means a lot of monkeying, get it unfudged and order up a full set of un-buggered units. I don't know squat about jetting for pods but it is not to be undertaken without the understanding that you WILL be at it for a while and may never find the "sweet" spot. But you gotta do what you gotta do. Look for another airbox assembly on flea-bay and bide your time, it will come.

 

i took the carbs apart again it is super clean inside and i did fine that the filter screan b4 the gas gets in the carbs was cloged it came from the contaner i had gass in but the carbs still had gass in them i also put the 124 jets in which are just a little bigger than it was so it should be fine and i put them all back together i will put the carbs on tonight after class and see if she will come alive and also i just bought a new battarie for my truck so i will use it and it will have full everything.... i guess we will see if the beast will come alive.. i sure hope so... i had spark with the other older batt but it was old so maybe bad amps but the new one will fix that. i didnt have time to get new spark plugs but i did pull them out and i put rags over the holes and laid the spark plugs out to dry and what is the proper gap for the spark plugs?

 

Plug gap: .028 ~ .032

Be sure the Spark Plug Wires aren't "Breaking-down" and arcing to Ground.

28 ~ 30 Years is a long time for a Spark Plug Wire.

 

ok i will

 

ok i put the cars back together and put them back on. i changed a little relay with a blue tab since i had another and the bike ran when i spraid gas in it so now i gotta finish welding the tank maybe today and see if it will run all by itself

 

Good luck!

 

Ok here is an update sorry for the long wait... so it runs (yay) all lights work and everything it idials high and when i turn the screw down it will stay high then i get low enough it just drops sharply and dies. if i hit the gas a little it will go up in rpms fine but goes back down slowly i took it for a short ride and it rides fine no problems. rpms run fine it reacts perfect with throttle and ya.. i didnt go fast so i only whent up to 3rd gear so it ran good for that. i did end up useing a 73 handa cb 750 gas tank and peck cock. it didnt have a place to plug in the vacum hose so should i just plug it up or what?? also found out brakes dont work when i took it out lol good thing i live in the middle of nowear lol so i fixed the brakes but still have to take out and test.

 

also my oil plugs the ones were there is one on each side on side/ bottom of motor one is broke/ craked and leaks slowly so ya i got to fix that

 

You need to get a vacuum cap for the nipple your petcock line comes from and cap it. Without it capped or the line plugged that cylinder is very lean if it's firing at all. Air is coming in without picking up fuel from the carb.

 

What you need to do to get it running correctly is pull the carbs back off, bench sync them and set the float levels correctly using clear tubing and fuel. Then vacuum-sync the carbs once they're back on; but you'll need to at least check your valve clearances first or you may not get a decent vac sync.

Then and ONLY THEN will you get it running. Going at it the way you are isn't getting you anywhere, as you're finding out; and it won't. You want advice on how to get the bike to run; you've been given that advice. Now you need to do it. You have to do it all, do it right, and do it in order or it will not run reliably, period.

Which may actually save your life if you insist on riding it around until you've rebuilt the brakes properly. It's a 120mph+ bike; the brakes are important.

 

what is best tool to use since i bet there are several brands and i fixed the brakes right after the ride so no problem there. also just to throw it out there maybe the idal isnt that high just i put a custom pipe on it and i have dino kit in the carbs so maybe it just sounds loud but when i rode it it sounded just like all the other bikes i have been on and felt as smooth as a new bike. i would give rpm facts but it didnt work so ya lol gatta fix that and maybe find out everything is fine just the pipe is loud. and just to clarify i new the front needed fixed but i figured the rear brake worked and it did but with the new pipe the brake couldnt go down far enough to engage it enough. but it is fixed now and i have new brakes on the front so brakes are good

 

alright so i got the carbs synced and everything. the bike still does not idial worth a crap i can use the choke and ajust it to idial around 2000 rpms and idk if that is because i put 125 jets in it or what would putting 120s back in it help at all? is this because i put pods on it? or is it because of the custom pipe ? i checked the list of stuff and it all seems good so idk. it also hates to start until i get it warmed up then i can turn it off and it fires rightback up.

 

My thoughts...

It does not start right away because the idle mix is wrong and it needs more fuel than is available. Your enrichment wells in the fuel bowl or passages in the carb may be plugged.

By 125's you mean main fuel jets? Your main fuel jet would have no impact on your idle setting IF your butterflys are closed properly to engage the idle circuit.

How many turns out are your pilot screws? Have any bigger pilot jets? It sounds to me like you need more fuel from it running better on "choke" which on these bikes introduces more fuel to the mix when working properly.

Your pods and your "custom" pipe have a large effect on your carbs and their jetting.

What's the exhaust consist of? Just a header? These bikes are quiet loud without a muffler.

 

You didn't get the carbs vacuum sync'ed if it won't run at idle, vacuum synchronizing is done AT IDLE.

If you have pod filters and non-stock pipes, rejetting will be necessary.

However it should still start.

So you took the carbs off, broke them down, and cleaned the emulsion tubes and the various jets, enrchment tubes and enrichment wells?

And set the float levels using fuel and clear tubing?

And then bench sync'ed?

Just out of curiousity, have you done a compression test on this motor?

Checked the valve clearances?

If the answer to any of the above questions is "no" then go back and do whatever it is you didn't do.

IN ORDER:

-Clean carbs
-set float levels, "WET"
-bench sync
-CHECK VALVE CLEARANCES AND ADJUST IF NEEDED
-running vacuum sync
-fine tune mixtures.

Leave anything out? Skip over any? If so, it explains why you're still not riding it.

 

the pipe consist of a extension of the hheader and an adapter to a 4 in pipe and it all is ss i cleand the carbs bench synch and then i did synch them but had to use choke to get the bike to stay at 2000 only thing i did not do is check valve clearence and i was realy frouning on takeing off the head i did look up ur forum to see how to do it an i was not thriled to jump into that. if i have to i will but if i dont i would be happy. also i have jets up to 134 or 136. breaks work great btw tested them out when we had some sun

 

Checking valve clearances is NECESSARY, and NOT difficult. Don't be afraid, your aren't really tearing into your engine, but if you don't do it, you will have to sooner or later :twisted:

You also haven't done a compression test, have you? If you don't know that result, you might be trying to revive a dead engine. Don't take "running" as a given, I've seen them run with a bad cylinder or two.

Also, check for air leaks in the carb-engine intake boots. You might be getting too much air, and it'll run with "choke" because you are giving it the right mixture, and idle fast because the butterflys don't regulate the airflow.

Lastly, take some time for punctuation/capitalization/paragraph marks in your post. Not to be a PITA, but your posts make it seem like you are rushing into things, and it'll make it easier for people to help you and future forum members who have the same issues, if your posts are a little easier to read. And we'll know you're being methodical and not just jumping from one idea to the next. :wink:

 

Here here Manbot! I love to see folks helping others to get their ducks in a row.
TheWoolf, you mention your exhaust is stainless (hard to tell) ?? Did you buy it that way or make it yourself?

 

I built the exhaust myself. I will put some pics up for all of you to see here realy soon.