ALT50 question

[ShelsDad]

I have a '83 Suzuki ALT50 and it wont idle without the choke. I cleaned the carb and set it back to factory adjustments and it runs better wide open now but still wont idle. it runs good if I hold it open with the choke off but soon as it idles down it dies. its got a new plug too, it was runnin fine but I was runnin it around on the back tires and it started doin this haha. this is my first ALT50, havnt got it all figured out so any help would help, thanks. :wondering

[Macs]

welcome aboard.


I would check to see if fuel is free flowing from the tank to the carb.

[ShelsDad]

well Im not too familiar with these older fuel shut-offs but this one has an ON (down) and a "PRI", when its on PRI it pours out and when its on ON it just kinda trickles. it runs the same on PRI and ON, and gas runs down the fuel line, theres a leak somewhere but I didnt figure that would have anything to do with it cuz its leaked like that ever since I got it and it and it was runnin fine. I havnt cleaned the tank yet cuz it does the same thing regardless the amount of fuel its getting. sound like anything you have dealt with?

[alt50guy]

ceheck you exhaust. Its probably clogged with crap. Mine would even start took off the exhaust and couldnt blow through it.

Cut the first 2-3 inches of insert of spark arrestor. It will run better reguardless

[ShelsDad]

I never thought of that, I'll do that tomorrow. even if that dont fix it, it will run better when it runs better haha. thanks.:beer

[ShelsDad]

Checked the exhaust and it flows free. havent cut the baffle yet, wanna get it runnin first but its on the list haha. Im stumped, yall got any more ideas?:wondering

[dcreel]

Could there be some reed warpage? Just an idea? That would explain the wide open difference compared to at idle.

[ShelsDad]

didnt even think of a reed. is it behind the lil 90deg elbow that the carb goes on? Im kinda not too familiar with 2-strokes haha.

[dcreel]

Yep.. thats it.. I just put new reeds and gaskets in a lt80. The old ones had a slight warp allowing air past them at idle. It used to start hard never without the choke. Now it starts with no choke almost immediately, idles better, and has way more power. I also removed the premix auto luber.

[99gsxr750]

I have an 84 lt50 (quad) and I don't think that has any reeds. I would assume yours doesn't either as the motors are probably the same. If it is the same, the carb will have three jets, a main and two stacked jets. Since it runs fine wide open then the main jet is ok. Check the stacked jets to see if they're clogged.

I removed one of the stacked jets and the spark arresstor (or at least it fell out somehwhere) and replaced the main jet with a 72 or 80. It performs better, and now can get out of it's own way. :lol:

[dcreel]

Check this out. $898 for a real nice alt 50
http://www.storesonline.com/site/1538094/product/84-ATL50
http://www.storesonline.com/images/site/common/en/image/imagewrap.img?picture.image.url=http://www.storesonline.com/members/1538094/uploaded/Photo095.JPG&picture.width.max=300&picture.height.max=0

According to bike bandit, it looks like it doesn't have any reeds. Wild. My Tri-zinger 60's have reeds. I just assumed the alt 50 would too.

[ShelsDad]

99gsxr750 is right an alt50 is a 3wheeled lt50, same motor. does bike bandit have the jets i need or do i have to find em somewhere else? if so, where?

[dcreel]

Bikebandit.com has the jets.
http://www.bikebandit.com/assets/schematics/Suzuki/SU0005_007.gif
1: FLOAT CHAMBER G
481384-001 Enter 0-99 $3.24
2: JET,PILOT (15)
(15) 474669-001 Enter 0-99 $8.60
3: JET PILOT (Z) #
474667-001 Enter 0-99 $4.87
4: M/J 57.5 (N1022
474584-001 Enter 0-99 $5.66
5: JET,NEEDLE E-6
474903-001 Enter 0-99 $12.13
6: NEEDLE,JET
481867-001 Enter 0-99 $9.12
7: SCREW
[MODEL P/R] 482877-001 Enter 0-99 $0.71
7: SCREW
2882-001 Enter 0-99 $0.71
9: THROTTLE STOP S
481500-001 Enter 0-99 $3.80
10: STOP SCREW SPRI
481555-001 Enter 0-99 $2.68
11: VALVE SPRING SE
482826-001 Enter 0-99 $3.76
12: CLIP,NEEDLE
482050-001 Enter 0-99 $2.66
13: DISCONTINUED
482700-001 Enter 0-99 $3.76
14: CARBURETOR CAP
483122-001 Enter 0-99 $2.94
15: STARTER RUBBER
483136-001 Enter 0-99 $1.75
16: THROTTLE VALVE
(CA:3.0) 482574-001 Enter 0-99 $15.14
17: TH VALVE INSP G
483063-001 Enter 0-99 $1.60
18: VALVE,NEEDLE
481731-001 Enter 0-99 $14.44
19: SCREW
[MODEL X/Y] 466029-001 Enter 0-99 $0.86
20: WASHER,LOCK
467215-001 Enter 0-99 $1.04
21: STARTER VALVE S
482180-001 Enter 0-99 $2.94
22: STARTER VALVE
482103-001 Enter 0-99 $8.08
23: PILOT AIR SCREW
481584-001 Enter 0-99 $6.78
25: SCREW
[SCREW] 466072-001 Enter 0-99 $1.04
26: WASHER, LOCK
[MODEL J/K/L] 467206-001 Enter 0-99 $1.04
27: DRAIN PLUG
481328-001 Enter 0-99 $2.94
28: DRAIN PLUG GASK
481346-001 Enter 0-99 $0.97
29: THROTTLE SPRING
482275-001 Enter 0-99 $1.08
30: SPRING
482274-001 Enter 0-99 $2.12

[ShelsDad]

OIC, haha I didnt even know there was 2 jets there when I cleaned the carb. I'll pull it apart and take jets apart and clean both this time and try that, if that doesnt do it I like the single jet idea, sounds like the way I need to go anyway haha. thanks for all the help:)

[99gsxr750]

Check for the intake and exhaust restrictors too. Mine didn't have either, but others say they've found one or both.
Also, I rejetted because I drilled holes in the airbox lid not just the missing spark arresstor.

[ShelsDad]

well, I just cleaned all 3 jets, the M/J was good lookin, I got the other 2 clean, it wants to idle now but dies soon as I give it gas. what can I do now haha:confused:

[99gsxr750]

well, I just cleaned all 3 jets, the M/J was good lookin, I got the other 2 clean, it wants to idle now but dies soon as I give it gas. what can I do now haha:confused:

Is that with the choke on or off? Those two jets are for idle and part throttle. Did you try removing one to see what would happen?

[ShelsDad]

it runs with the choke on, and it'll idle for a short period of time with choke off and will run from half throttle to full throttle with the choke off but still slugish. I'll remove a jet and see what it does

[ShelsDad]

it'll idle now with the main jet removed without the choke but soon as i give it gas it floods and dies.

[99gsxr750]

Remove one of the stacked jets. The main is probably fine since it runs from half to full throttle. The problem is with the pilots as they are from idle to half throttle. If it runs part throttle with the choke, then it's still not getting enough fuel.

[ShelsDad]

sounds like I need to start ordering parts haha, everything is as clean as its gonna get. prolly need #4, #5 and #6 on the bikebandit.com Schematic, however I didnt see #2 or #3 in my carb, maybe overlooked them, could those two be causing a problem? sorry for all the questions, Im not very familiar with carbs. Thanks for the help.

[99gsxr750]

2 and 3 are the stacked pilot jets, they are your problem. You have to remove one to get to the other. Is the carb stock?

[ShelsDad]

crap haha, I have been messin with 4 and 5, Ima go look for 2 and 3 now, and ya the carb is stock everything is stock. well see what happens lol.

[ShelsDad]

well that was it I think, there was only 1 jet there tho. anyway now it runs but floods when I give it 1/2 to full throttle, due to me over cleaning the M/J (#4),,, with a drill bit haha, oops. that was the problem tho, good call:beer , still need to find a #4 jet.

[ShelsDad]

alright I found a 65 main jet, that was the smallst they had. it idles fine now but dont have anything after 1/2 throttle, do I need to order the stock 57.5 or ya think I can make the 65 work somehow? I havent modified anything yet eather, like exhaust or air box. it runs the same w/ the air box on or off also. Im goin :crazy: cuz this lil thing haha.

[ShelsDad]

oh it idles awsome now, it just falls on its face after 1/2 throttle.

[99gsxr750]

alright I found a 65 main jet, that was the smallst they had. it idles fine now but dont have anything after 1/2 throttle, do I need to order the stock 57.5 or ya think I can make the 65 work somehow?

I would get the correct jet. This way you'll know that's not causing the problem.

[ShelsDad]

I'll do that, they'll order one and trade me. still wanna check my exhaust sometime tho, thanks for all the help so far :)