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View Full Version : 200x auto X runs and idles good but hard to start? I cant figure it out



nicker71
02-08-2014, 04:42 PM
Ok, where to start. I have a 84 200 auto x that I built a few years ago. It has a 185s bottom end and a 200x top end. Well last summer it started smoking more than I like, so this winter I tore down the engine and sent it off to get a rebuild by G&H discount atv. The head was fully rebuilt along with a bore job and piston. Prior to the rebuild the auto x was always hard to start when cold and not the best idling machine but ran fairly well. Once it was warm the engine was easier to start but still not the one or two pulls which I would like. It would sometimes idle but I would have to turn the RPM's up higher than normal to achieve this. I never checked compression before I torn the engine down for repairs, but it was hard to pull.

So I get the new engine put all back together carefully following the honda manuals torque specs, install the engine and hook all the wiring back up, fill with oil, etc.. Before attempting to start for the first time I double check the timing and its perfect, I check for spark on the NEW plug, looks good. (Blue spark). Double check the CDI pulse gen timing and adjusted it a little, and double checked the valve clearance and it was good too. I must have pulled it 15-20 times before she fired up. I let it run for a couple minutes, keeping my hand on the throttle making sure she wouldn't die on me, then I shut it off. I did this once again after it cooled down for a while and still hard to start. while in the middle of all the pull starting I removed the plug a couple of times to see if it was getting fuel and it seemed dry. I tore the carb down and checked the jets, they looked good, so I put it back together and tried it again. I took probably 10 pulls and fired up, I ran it for a minute then shut it down.

I rebuilt the carb a couple years ago and it didn't really change much so this time I just bought a cheapo ebay carb. I've heard both good and bad things with these, but for the most part I always had good luck with them. Over the years most of the time when I would rebuild a carb it still wouldn't idle afterwards. Then I'd slap on a cheapo carb and off course the motor would idle just fine. Well so I bought me a 200x carb from ebay and I placed in yesterday I prob pulled it 5-8 times before she started, I played around with the choke (it was 30degreesF outside) and adjusted the idle, I kept my hand on the throttle to make sure it wouldn't die and once the engine was warm it would idle very nicely. I did a couple of these 10 min heat cycles each time it would take roughly 5-8 pulls with the choke on and me giving it throttle while pulling the rope. when it first started it wouldn't want to stay running(30 degreesF?) but once it warmed up a minute I would turn the choke off and it would idle nicely. I've now done a couple 10-15 min runs around my home while following proper break in procedures. It idles perfect when warm and runs good at all RPM's. BUT, I spent a fair amount of money in this thing and I would really like for it to start up a little easier when cold. It seems to me, but maybe I'm wrong that this machine should start up a little easier??? It still seems hard starting much like before the rebuild when cold, does anyone have any suggestions? And should it start up, without me giving it throttle??

It has a new filter with light coat of filter oil, fresh 93 octane pump gas. new spark plug gapped .028", I also cut the spark plug wire down some and made sure it had good connection. It has a clear fuel line and I can see gas pass to the carb once I turn the petcock valve on.
After my last 15min ride I took out the plug and looked at the color, looked light brown so I feel the jetting is good too since it never popped or cutout. The mixture screw was 2 turns out.

I was thinking about trying a new China CDI mod trick next to see what would happen.

Thoughts or suggestions??

O yeah I checked for air leaking around the intake boot and carb with brake cleaner and never noticed anything either

Heres a picture of the ugly thing

http://i156.photobucket.com/albums/t27/nicker71/IMG_1556_zpsac29f10f.jpg (http://s156.photobucket.com/user/nicker71/media/IMG_1556_zpsac29f10f.jpg.html)

JustEnough
02-08-2014, 04:53 PM
Hard to start cold usually means that it is time to for a valve adjustment.

I have been rebuilding original carburetors and I have found that the exact model carb for that year and model top end works best. Unfortunately this list does not include the 200x.

186340 186341 186332

DohcBikes
02-08-2014, 06:00 PM
5-8 pulls isn't really all that bad in the cold.

I would try another 1/4 turn out on the fuel screw, and possibly try a lower octane fuel, 93 is likely not necessary for your setup. Lower octane fuel has more energy in any given amount and that might help the cold starting issue.

nicker71
02-08-2014, 06:03 PM
Hard to start cold usually means that it is time to for a valve adjustment.

I have been rebuilding original carburetors and I have found that the exact model carb for that year and model top end works best. Unfortunately this list does not include the 200x.

186340 186341 186332

I checked the valves and they are .003" for each one.

It might be possible that I'm using the 185s cam instead of the 200x. When I swapped out the topends for this setup a few years ago I remember having some damage on one of the cams. What I don't remember is which one. Is there any differences between the two? And if so is there any easy way to tell them apart? I wonder if this maybe causing my hard cold starting problems?

Scootertrash
02-09-2014, 09:16 AM
According to the 200X manual I downloaded here,the pilot screw should be 1 3/4 for 1983 and 2 1/4 after 1983.

Did you adjust the pilot screw after it was warmed up and running? With the machine warmed up and running turn the pilot screw in slowly until the engine starts to idle down then turn it back out until it starts to idle down counting the turns on the screw, turn turn it back so you are roughly in the middle. I usually just shoot for the highest idle I can get out of the pilot screw. Then readjust your idle speed with the throttle stop screw.