1974 Alsport Trisport RTS 340 SL Restore / Rebuild thread

Rebuild the walbro or get a different carb


  • Total voters
    25
Hey buddy. I'm in. Nice job on the trike. And great job posting your progress. I'm hoping to hook up with some of your connections from this site for advise on my alsport trisport SL build. Seems like there's an awful lot of knowledge about these trikes here.
 
Got a front brake worked out....kinda lol.
Also got my carb in so this weekend hopefully I'll be posting wheelie videos Lmao.

And got another project to slow me down haha.
 

wjustice

Well-Known Member
What carb are you using. I had 2 walbros and a tillotson and nothing but trouble. Could get then to run but horrible to start. Finally gave up and got a new mikuni. I advoided it till i couldnt take hurting my ribs pulling these engines again. Huge difference. Unless someone can show me something i was doing wrong, I'll switch them everytime now.
 

wjustice

Well-Known Member
I think my tilly( an HD) had a bad power valve. It looked like someone drilled the welch plug and damages the valve. The walbros? They ran ok but did not want to start. Only problem I've had with the mikunis is the bowl dries up if they set. They're ok for a week maybe 2 but more then that and you have to prime or ether to get them going
 
Got ya. Not sure what to do. I was getting spark but not sure of quality. Didn't look very intense and was white....not sure if that's bad or good or what to do about it wither way.

Definitely can't afford to buy a new carb or any electrical stuff right now.

I've sunk over a grand in it and I haven't even heard it run for more then 10 seconds. Still have to get it running just to find out if it needs anything else besides the crazy expensive brakes.

If something doesn't get drastically better soon I will be selling it and giving up the restoration dream.
 
I don't have any spray but earlier today it started and ran for 10 seconds. Last night I flooded the crap out of it. Came out today and drained the case. Pulled pulled pulled and finally got it to fire.
Ran for 10 seconds blowing fuel that had collected in the exhaust out. When the fuel cleared up it started reving higher and higher until I got nervous and killed it.

Could get it to periodically start and die a second later. Trying to give it gas to keep it going would kill it immediately.

I think the needle and seat in the carb are screwed causing it to flood out.

Not sure about the spark quality. Maybe someone can enlighten me on that.
 
Well what you said about It reving up higher and higher is worry some to me. Have you done a compression check ? or pressure checked for a leaking seal. Often just a bit of running will help seals and things like stuck piston rings. But a compression check is helpful in finding out things
Steve
 
4 strokes have carbs but you dont have to keep adjusting them when they run hot or cold. We have never had luck with 2 strokes... Especially the dinosaurs these things use.
 
we've got many vintage 2 strokers that run like a top.with both walbros and tillys.never even had to rebuild a carb yet.
our raiders fired right up this season after sitting for 8+ months. our rts sat for who knows how long before we got it.runs strong and starts fine and only thing I did was clean and adjust the points and new plugs

like steve says some of the seals may be dry and sucking air

you'll get it going
 
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Steve, I think the problem is that where he lives or even where I live 2 strokes are usually sitting for 30+ years before we see them. The same 30+ year old ones you see have been used throughout the years.... Ours were just put away out of frustration...... Trikes are a labor of love on a good day.
 
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