You might be right Marty. Don't know it I'd chance it though.
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My rebuild journey. (old title: Future owner - Help me identify this 650.)
- Thread starter Sudonate91
- Start date
You don't have to worry about the heavier oils (40 and 50wt.) having those anti-friction additives. They only put them in the thinner oils (10, 20, and 30wt.). Personally, I use the Walmart brand, have been for years now, and in all my vehicles too. Due to the rather crude filtering system on this bike, it's best you change the oil often, like every 1000 to 1500 miles.
Exactly what size jets to use is sort of an experimentation but since so many have done this and reported their results (and jet sizes used), we can give some general recommendations. I'd start with 2 up on the mains (132.5 stock to 137.5). If you do have issues with the transition from idle into midrange then you'll want to increase the pilots one size too (42.5 stock to 45).
The BS34 carbs on your bike were the last set used and the most highly E.P.A. stifled. They came set up from the factory pretty lean, almost too lean, to pass emissions standards. Any change at all to intake or exhaust usually requires some jetting changes. You may get away with some minor changes on some of the earlier models with their more richly jetted and less E.P.A. mandated carbs, but not on any of the BS34 equipped bikes.
Exactly what size jets to use is sort of an experimentation but since so many have done this and reported their results (and jet sizes used), we can give some general recommendations. I'd start with 2 up on the mains (132.5 stock to 137.5). If you do have issues with the transition from idle into midrange then you'll want to increase the pilots one size too (42.5 stock to 45).
The BS34 carbs on your bike were the last set used and the most highly E.P.A. stifled. They came set up from the factory pretty lean, almost too lean, to pass emissions standards. Any change at all to intake or exhaust usually requires some jetting changes. You may get away with some minor changes on some of the earlier models with their more richly jetted and less E.P.A. mandated carbs, but not on any of the BS34 equipped bikes.
Gotcha. Learn sumpin' every day.
Sudonate91
XS650 Addict
SN Plus is designed to protect against low speed preignition in turbo charged motors. Copied from what I looked up:
How does API SN PLUS address LSPI?
A motor oil works thanks to an ingredient called the engine detergent, which keeps soot, dirt and other debris from interfering with the lubricant. Traditional motor oils use calcium and/or magnesium for this. However, research has shown that oils with a lower calcium and higher magnesium composition lead to fewer incidents of LSPI. Oils that meet API SN PLUS standards use more magnesium for the engine detergent, making them far less susceptible to LSPI.
Not sure how this would impact wet clutches but I wouldn't risk it, personally.
How does API SN PLUS address LSPI?
A motor oil works thanks to an ingredient called the engine detergent, which keeps soot, dirt and other debris from interfering with the lubricant. Traditional motor oils use calcium and/or magnesium for this. However, research has shown that oils with a lower calcium and higher magnesium composition lead to fewer incidents of LSPI. Oils that meet API SN PLUS standards use more magnesium for the engine detergent, making them far less susceptible to LSPI.
Not sure how this would impact wet clutches but I wouldn't risk it, personally.
Since you’re going to be futzing with this bike for a while, just get the Walmart 20W50. It’s cheap, so you won’t have regrets draining it.
Sudonate91
XS650 Addict
I'm researching how to fix the front brake. I think I can rebuild the caliper and replace the hose with a braided steel line. I'm really concerned I won't be able to pull off the master cylinder restore. I read this thread http://www.xs650.com/threads/master-cylinder-rebuilding.7862/ and I don't seem to have some tools like the snap ring pliers and other things. I'm wondering if it would be more cost effective/safe I'd I bought a new mc. Any suggestions? I see 14mm is the bore size to go. Ebay has tons of cheap 15$ ones but I feel that's a 'you get what you pay for' and I'll die on a blaze of glory someday when my brake goes out...
So what do you suggest I do with the current mc? What is a good replacement for it?
So what do you suggest I do with the current mc? What is a good replacement for it?
How good a mechanic do you want to be.... a "part swapper" or an old school mechanic? No offense meant to you parts swappers out there.
On a difficulty scale of 1 to 10, the MC is prolly a 3 or 4. Snap ring pliers ain't that expensive.
'Sides... look how far you've already come.
Should have added.... there's a good possibility the MC bore is pitted beyond use.... in which case you'll be getting a different one. You got nothin' to lose by trying.
Motion Pro has a mc snap ring plier that makes the job easy. I don’t think it’s expensive.
You mentioned earlier getting a rebuild kit from Mikes. I've no experience with it, but I'm inclined not to trust it. People don't have much luck with rubber bits from them. My go to for brake rebuilds is K&L. Good Japanese quality. Here's one on Ebay.
If you are going to replace the MC, you might consider one just slightly smaller. While the Japs made pretty good disc brake systems back then, they hadn't quite figured out the best ratio in size between the MC and the caliper pistons it was pushing for best brake "feel". The 14mm size Yamaha used here was just slightly too big. Replacing it with something in the 11 to 13mm range will give improved "feel" and modulation. But, there's nothing wrong with the stock 14mm size, it works OK. So, you could still use it if you just wanted to do a rebuild. I'm just saying that if you do decide to replace the whole thing, might as well downsize it slightly. I have an 11mm on one of mine, a 1/2 (12.7mm) on the other. Both improved the "feel" but I'm more partial to the 1/2" because it did so with less additional lever travel.
Remember that the Yamaha master cylinders do have a left hand thread for that right side mirror. If you choose an after market master cylinder, that may be a consideration.
Rebuilding the caliper isn't hard. Often you don't need new parts. Just a tear down to throughly clean things up. Once apart you inspect the parts to see what you need. Pitting on the ;piston can cause leaks so if pitted to badly they should be replaced. Mike's XS has stainless steel replacement that work well.
The groove in the caliper the seal fits in needs to be very clean. Any crud in the groove prevents the seal seating fully and this can cause the piston to bind.
Leo
The groove in the caliper the seal fits in needs to be very clean. Any crud in the groove prevents the seal seating fully and this can cause the piston to bind.
Leo
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Sudonate91
XS650 Addict
This is the road rash it has. It has seen better days. The brake line almost seems newish. But it brake lines are the same as trucks - its bad. I actually replaced the brake lines on this same grandpa's ford f150 after it was sticking reaaaaaal bad because the soft hose eroded causing bad flow.
I would love to 'fix it' and say I did. But it seems complicated. By the time I get the parts, tools, and whatever else - the cost might be similar to buying new.
I would love to 'fix it' and say I did. But it seems complicated. By the time I get the parts, tools, and whatever else - the cost might be similar to buying new.
Sudonate91
XS650 Addict
. Also great thread thanks for linking it.
If you do downsize the MC to a smaller bore one, don't toss the factory MC, someone will gladly take it off your hands
