I recently installed a tach on my DS, 2001. After the install, the bike didn't want to start. It used to start up every time when I hit the start button. It just turns over but doesn't want to start. If I blip the throttle when starting, the bike will catch and I have to keep blipping the throttle to keep it running or it will cut out.

I charged the battery to make sure it was fully charged. When I get it to start, it backfires continually each time I let off the throttle. I have dual FCR 39s installed on the bike. I pulled the filters off and I noticed that it seems to only want to run when the AP is shooting fuel straight into the carbs itself. I noticed when I was at Pismo that I didn't have quite as much power, but now this is ridiculous.

I checked the valves and the intake valves were way tight. Took it in to have them clearanced before I installed the tach, but now I just did the job myself. They were .3mm too tight. One exhaust valve was right on and the other exhaust valve was at .2mm. I now realize how easy the job is to do it myself. I was hoping that this would fix my problem, but I still can't keep the bike going.

It only wants to run wide open, which is great, but I would like to trail ride as well. The slides are pulliing up and down with the cable. I've had the carbs on for 6 months with no problems. The bike just wants to sputter till it gets over 6000 rpms. Also repacked the exhaust to make sure it wasn't somehow clogged up.

Dustin

2001 DS 650, no motor mods, dual fcr 39s, pami CDI, CT exhaust, added tach

 

Mine wouldn't idle for nothing when I first put them on.

Make sure your fuel screws and slow jets are tuned properly.

Theres some great tunning info for these carbs out there. Do a search.

 

When I first put the carbs on, they ran great. I guess the pilot screws could have come loose? I haven't heard anyone mention this before and have never experienced this. I will have to check them.

 

go through each circuit with compressed air and carb cleaner- my guess is you've plug something up.

 

Al is this the one you were thinking of dual 39's it is interesting but the thing you want to be sure to read is the" tunning guide" it's a link you can click on this page.
Good luck

 

Yea, I had that one printed out too. I had gotten these things dialed in and thrown it away. Now when I put this thing back together, I may have to tweak it a little. I may even end up on Alky!

 

Has anyone tried the 41 Fcr's yet?

 

So do you guys think this could also be an electrical problem? Like a bad CDI or anything? I put on my old carb right now but I can't exactly fire the beast up at 2am. She's just too damn loud. Hopefully she'll run just fine so I only have to worry about the carbs being gummed up somewhere. If she doesn't run fine, then what? Compression test and make sure I didn't burn up some valves?

I was really hoping that clearancing the valves was going to take care of everything. I can see some carbon build up on the intake valves when I look down the intake on the head. One looks more carboned than the other on the top side of the valves where the stem is.

 

kmduner has the 41fcrs

 

Sounds to me like you PilotJets are clogged up. As you know the PilotJets take care of the Idle to around1/4 throttle. It is very easy to clogg the pilots up. with trashy gas, or if a couple rains of sand ot through you airfilter.





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