XR350 Breaks Down Under Revs

[OrgKaos]

I have an '83 XR350. It takes a while to kick over, but once going it idles but sick and under load it's breaking down. Is it timing? Spark? Or carby problems? But none-the-less has half decent spark. I have gone through and cleaned carby... checked for spark...

It's got no electicals besides kill switch. I would also like to know if it has a wet fly wheel.

Thanks for your help! Greatly appreciated.

:p

 

[john stu]

hows your valve adjustment?

 

[OrgKaos]

Valve Adjustment

I don't have a manual, so I wouldn't have a clue on what the valve adjustment is meant to be. Some handy hints would be nice...? Other than that, when it's running, and it stalls, it back-fires through the carby.

I was talking to my old-boy and he seems to think it's timing for it to be back-firing through the carby when it stalls.

:coocoo:

 

[Ol'89r]

Timing is fixed and can't be adjusted without modifying the pick-up coil mount.

Check the valve adjustment first. .002 on the intake and .003 on the exhaust. Checked at TDC on the compression stroke.

Remove the spark plug cap by unscrewing it from the plug wire. Take a flat blade screwdriver and remove the brass screw in the center of the plug cap where the plug goes. Remove the little spring and resister under the screw and replace the resister with a piece of copper rod the same size and length of the resistor. Before screwing the cap back on, cut about 3/8" from the end of the plug wire to expose fresh wire. The end of the plug wire can become oxidized.

If it still breaks up on top, remove the right side engine case and inspect the pick-coil. Those engines run hot and the insulation on the pick-up coil can crack and expose the wiring.

Also, check your intake manifold. Move the carbs around by hand and look for cracks in the manifold rubber.

If none of that helps, check your carbs again.

If I remember correctly, the flywheel is wet.

Hope this helps. :cool:

 

[OrgKaos]

cheers i dont have time till the weekend to look at it. But i know what u mean cheers ol'89

 

[fletcher]

sound like the same problem i had , try changing the coil, i did and it was perfect , but now i am going through a coil every 2 months so i fixed one problem and started another , i done what ol89r said with the lead and resistor and it does work , try it first if not try the coil and if it does fix then just see how long it last,(forever hopefully).

 

[1BAD250]

if you think you have a electrical problem im selling a hole complete set up on the bay look up xr350r the bike was a 85 but i think its all the same hury the parts end today.

 

[OrgKaos]

xr350 mungrel to start

I have my mates xr350 (83).I have just adjusted the valves cleanded the carby n played with the coil but the bloody thing is still a mungrel to start, when she is going she is great but its getting it going is the hard part. It roll starts easy enough but hard to kick over. When i do kick it over its like it looses its compression n the kicker doesn't always cum back up, could the decompression leaver have some thing to do with it since it is not hooked up.she also starts first kick some times. Any help would go a long way :bang:

 

[OrgKaos]

thanks 4 all help i fixed the problem but now its a bitch to start i think its the coil just wondered what coil would work i have a xt250 coil 71 modle would that work or does it have to b a honda part?

 

[Ol'89r]

When i do kick it over its like it looses its compression n the kicker doesn't always cum back up, could the decompression leaver have some thing to do with it since it is not hooked up.QUOTE]


Yes, it makes it much easier to start the bike if the compression release mechanism is hooked-up and properly adjusted. The kick starter has a mechanism that actuates the compression release on tick-over. There is a cable that goes from the mechanism lever just behind the kick starter to the compression release on top of the head. If this cable is missing or not adjusted correctly, the bike will be a bear to start. It is supposed to release the compression on the first part of the kick stroke and then click off for full compression on the rest of the kick stroke.

Hope this helps.

 

[jason33]

i think its easier to start with out the decompression cable hooked up- if you can kick it in sequence-
it also allows the air/ fuel to compress and mix completely- unlike it escaping through the exhaust valve-

try bigger pilot jets- 1-2 sizes thats all - check the needle position- mine are in the 2nd position-i have the twin carb one

yea the damn kicker will stick if the spring isn't wound tight enough- or is wore out
(since yours is unhooked take the kicker off and wind the shaft counter clock wise a lil- JUST a little)
the the decompression lever in the crank case will only go togerther 1 way and move right-
if your kicker is positioned too far forward on the shaft it will bust the little stop tab in the case under the kicker shaft!!!!
be carefull----------
also the decompression lever sits on the kicker shaft in 1 position or the valve will BE OPEN!!!!!!!!
this also could be a problem that your haveing----yea i have the book-lol
i do agree even with the book its a pain in the arrrs--lolol

 

[jason33]

get 1 new from dennis kirk- they have different coils and are inexpencive
the honda 1 listed is 9.99- part#-20-1281
1-800-969-7601