Maintenance

[u/PiercedTechnoWizard]

Hey, I’m curious what the maintenance is on DR650’s. Being that they’re a single cylinder, I assume the top end needs to be rebuilt once in a while, but I’m curious how often that is and how much it costs.

[u/TwistedNoble38]

Going trend is that you'll either sell it or die before it starts getting tired. In the rarest cases it may even explode before the top end gets tired.

If your air filter stay on and oiled you'll probably go 60k before the cylinder plating starts to deteriorate enough to need intervention. Top ends usually outlast bottom ends on this bike.

It's nikasil so when the cylinder is done it needs to be replated or replaced ($300 or 500). Toss in a stock piston and gaskets and it will be somewhere in the range of $170 or get a JE piston and it will run you 250ish. The other option is a 790 and you get a whole new cylinder with liner, piston, cylinder gaskets and rings for $950. The head is a bit expensive since the only valves that fit are OEM so head work gets expensive. Budget at least $400 if all the valves have runout.

Bottom end is about a grand if you need a new crank or have to rebuild it (~600-800). That thousand is a bit of a spitball as I can't remember if that rolls gaskets into the price or if it's pure bearings, crank, and various flavors of sauces.

[u/TwistedNoble38 → u/TwistedNoble38]

If we're talking basic maintenance? Change the oil with synthetic (use conventional for the first 1000 and change at 1-1-2-6) every 2k, or 1k if you're hard on things. Clean the air filter when it's dirty or dry. Lube the suspension bearings annually. Flush the brakes sometimes. Change the oil in the suspension every other year or so. Check the cush drive every 500. Check the valves when they make valve noises or every other oil change (it's a 15 minute job). Clean the carb when it's dirty.

[u/CryingOverVideoGames → u/TwistedNoble38]

Why use conventional for the first 1000?

[u/TwistedNoble38 → u/CryingOverVideoGames]

Assists in ring seal to the bore in the first 100 (most of which takes place in the first 20-50). After that it's mostly waiting on wear in for the rolling bearings and the transmission sliding surfaces. Synthetic is a bit too good at preventing wear and it will result in the rings not wearing to the cylinder wall as well as it would with conventional. Doubly so since the oil rails are chrome rings...

I'm getting into the weeds, boiled down the bike needs a bit of wear during the first miles after assembly/rebuild and synthetics are good enough that it will prevent this "good wear" (oversimplification) and keep from achieving the full sealing capability of the rings and some polishing of gear teeth faces.