engine

Hi, Recently got back into the xs650 scene after picking up a clean 1983 heritage special that was stored for a good periods of time... after getting it running I noticed the left cylinder is cold (exhaust). I've check spark and it's all good,compression is also good and new plugs. Cylinder...

How far is too far? How far is enough? I've had a few xs650's and each have their own quirks. I've yet to do a full motor rebuild from the ground up but I'm getting closer to pulling the trigger. I just wonder how far I can go in the performance department while not sacrificing...

I finally got off my ass and pulled the top end apart to replace the cam chain and get my valves done. My cylinders are within tolerance so no boring required but I'm having a bitch of a time finding stock rings where they don't want an arm and a leg for them. I found these...

Hi all, I'm wondering if anyone is using the Megacycle 250-30 cam? They say it needs piston and valve guide modifications!? Anyone know what specific modifications are required? Cheers

I have just realised that I've not put this part where it's meant to go - having already reassembled my engine as a first timer. What is it and what does it do? Feeling depressed at having to pull cam chain and top apart again.:wtf:

Hello All I tried doing the starter fix (pinching the bendix in a vice) and am in the process of putting everything back together. The cover is getting bound up back by the kickstarter and a little bit at the front. I don't think I pulled the kickstarter out when I pulled the cover off but...

I am getting ready to button up my top end after freshening everything up and have noticed significant wear/damage on my valve adjuster screws. I have been reading through the extensive archives on the Elephant Foot mods and the various options available out there. I have basic shop tools...

Ok. Lets imagine that there is a programmable ignition that has the option to use vacuum advance to control ignition based on engine load. Vacuum advance should increase mileage when "just cruising". Maybe not much but some anyway. How would you use the engine load signal to change the...

When i put my baby away last Winter she had developed quite a loud ticking clicking rattle noise . As it was too cold and wet in November to work outside I decided to sort the problem out in the following Spring. Well its now mid Summer and I may finally be in a position to snatch some time...

hey guys need a couple of expert opinions here. so i have a 74 xs650, i recently straight piped it and shortly after noticed that there was a very excessive amount of oil coming out of the breather tubes at the top of the motor. enough that it is a fairly constant drip coming out while i ride...

Hi guys. Im testing some components for my 1980 xs650 motor I will be putting in a go cart. (wheel barrow hot rod) My rotor is good at 5.3 ohms, but using curley's charging guide, When I test the stator, on the white wires im getting 1 ohm on one white wire, and .8 ohm on the other two. Curly...

I've had a pesky exhaust leak with my xs... It leaks right at the flange. I cleaned the surface with sandpaper, and I've tried a couple new sets of gaskets. tried double stacking them, even rtv copper as a last resort, but nothing will seal it. Torqued to spec every time. Anyone else have this...

I finally had enough with the rattly motor. Convinced it was a cam chain guide gone the way of the dodo, I pulled the motor and found the following: It sure is easy to push now! I really can't find anything wrong. When my old Seca turbo cracked it's front cam chain...

Hey guys, new to the forums here. I'm having an issue with my 81 xs. I just converted it to the xscharge pma, and installed the new advancer unit and pamco ignition. I set the base timing at idle, but it doesnt seem like my advancer is doing anything. Once I have the advance rod tightened on...

Hey gents, just spent some time reading through threads in relation to this problem. Using a timing light I get a nice consistent view of my timing mark right at the tdc mark on my sticker. When I rev up the mechanical event weights throw out consistently at or around 3000 rpm but my timing...

Good Evening all, Just signed up to what looks like an amazing site with lots & lots of information. Ive just Purchased a XS650 Hardtail Bobber...however the guy who sold me it removed the battery as it needed charging...While doing this there was a spark and probably a short and now the bike...

I found this and it better describes how I break in an engine. http://www.mototuneusa.com/break_in_secrets.htm I do it this way. Works for me. Leo

Alright, just trying to brain storm why my bike isnt running the best and maybe someone has an idea of something I could change/try. Bike seems run just fine until im in 5th gear trying to get up to higher speeds. It just doesnt want to get above 55 mph. It revs out and doesnt want to go any...

Hello everyone, a quick question for the community... What do you think if this gear from my crank assembly? Is it too far gone, or within usable condition?

Hey guys, I was wondering if it is possible to take the bottom half off the motor case off without taking the whole top end apart. I have a few old cracks around the two angled bolts right in the middle of the case in between the two oil plugs that are leaking. I have spare parts to replace the...