Maintenance Observations

A short sto­ry of deferred main­te­nance, dirty carbs, and bro­ken kickstarters.

At the last tri­als a few weeks ago, I noticed that my ’04 sher­co was becom­ming a lit­tle hard to start and was occa­sion­al­ly kick­ing back dur­ing starting. 

So I got on the horn and ordered a few parts for some main­te­nance, and some improve­ments. One of the improve­ments was a 9-tooth cout­ner­shaft sprock­et to slow the thing down a lit­tle. So I changed the sprock­et and was going for a short test ride. Got the bike start­ed, but it wouldn’t run with­out the choke on. uh-oh, this doesn’t sound good. it died, and when I re-start­ed it, it kicked back, and I heard some­thing go ‘ting!’. When it imme­di­ate­ly died, I looked down for the kick­starter, and the end of it was gone! When the bike kicked back against my foot, it snapped the ‘foot’ part of the kick­starter off! cap­i­tal CRAP. lucky i wasn’t wear­ing trainers! 

so. next step is to order some parts. so i place an order for some new spark plugs, a kick­starter , and just to be safe, a cou­ple of woodruff keys. The woodruff keys are because one of the things that can make a 2-stroke kick back is bad tim­ing. on a mod­ern engine like our bikes, the only way the tim­ing gets inac­cu­rate is for the woodruf key to shear and the fly­wheel to slip on the crank­shaft. Maybe that’s what happened…

While wait­ing for my parts, I pulled the carb, the air­box, and the fly­wheel. The woodruf key was good, every­thing looked clean inside the engine. The carb was a dif­fer­ent mat­ter though, crud in the float bowl, and and appar­ent­ly a plugged pilot jet. a good clean­ing lat­er, i reassem­bled and rein­stalled the carb, and wait­ed for the parts. 

When the parts arrived, I put a new woodruf key in, just on gen­er­al prin­ci­ples, poped in a new spark plug, and reassem­bled enough of the bike to start it. Got it start­ed, tuned the low-speed jet a bit, and it runs great. 

So the morale of the sto­ry is: buy your bike a new spark plug and clean it’s car­beu­ra­tor every few years, it will thank you. oh, and be very care­ful kick-start­ing a bike in trainers!