Strange noise from engine after tightening chain

[Red'09250]

Hi everyone,
I just tightened my chain today and decided to take it for a quick test drive around the parking lot. It would just be a quick test to make sure I didn't screw something up major, so I didn't bother to put on a helmet. I noticed a noise coming from the front sprocket/engine area. I only noticed it when I was riding by a fence (that reflected the noise), but I hadn't noticed it before I had tightened the chain either. It doesn't sound bad (not like any real damage is being done yet), but I'd hate to take this thing out on the road and have the chain snap doing 40mph in traffic.

I wasn't wearing a helmet, which I usually do, so that definitely has an effect on what I could hear. The noise has nothing to do with engine RPM, just the speed of the bike (and thus the chain).

Does anybody notice a noise like this on their bikes too?

Also, sometimes there's a strange whistling noise coming from my gas tank. It stops when I open the lid, but then starts right back up again after I close it. WTF is this?


ok, i'm joking about the gas vent noise. but I'm pretty concerned about the chain. Any input on this?

[DerTeufel]

How much slack is in the chain? If it's less than 1.2", loosen it up a bit.

[Red'09250]

yes it's less than 1.2", it's about .9". I thought the specs were .8 to 1.2

[DerTeufel]

Yes, they are..did you adjust at the chain's tightest point? As for the noise, can you describe it? Chains can be pretty noisy.

[Red'09250]

Its tightest point? I don't follow you. I adjusted it roughly in the middle between the rear and front sprockets.

Sounds like a rattle, almost like something is rubbing against the chain near the front sprocket. That doesn't make any sense though as all my adjustments were at the rear sprocket.

[DerTeufel]

When adjusting the chain, you slowly spin the rear wheel until you find the point where the chain is the tightest (less slack). When you find that point, you adjust the chain. I adjust to the looser end of the specs.

A chain is going to make some noise

http://www.youtube.com/watch?v=uRBkRKDlMtA

[Red'09250]

Are you adjusting in gear or in neutral? I thought you were supposed to adjust it in neutral.

[DerTeufel]

Adjust when the transmission in neutral. Watch the vid..it explains everything.

[Red'09250]

Ok, great. Thanks for the info, I'll go out and double-check it in the morning.

I also noticed that the noise from my bike is pretty similar to the noise in the video when he was rotating the tire, so I'm not too worried about it anymore.

Thanks again for your help!

[DerTeufel]

No problem.

[randomwalk101]

It's all in your head
Posted via Mobile Device

[VeX]

Make sure you keep your chain lubed... A well waxed chain will run a lot quieter then a crusty neglected chain . And as for the slack, It's wiser to err (I like to say err) on the loose side then tight side. As long as you're not pushing 2"+ of slack it's not going to come flying off. I always put it to (as DerTeufel mentioned) about 1.2" and tighten it if it gets to 1.5".

If the chain is TOO tight it will cause a kind of whirling noise and can prematurely wear out the output shaft bearing and seal (bad bad news). And good lord I had to scroll up 2-3 times to get the spelling of DerTeufel right!

[Red'09250]

Originally Posted by randomwalk101

It's all in your head
Posted via Mobile Device

hah, you're probably right. i'm just chain-locking-up-on-me-at-50mph-phobic i guess.

i'll check it tomorrow and make sure it's not too tight.

it makes sense that too tight is worse than too loose. if i haven't been measuring it right all along it's probably a lot looser than i think it is

[Red'09250]

Well I measured it again, it was all well within specs (between 1.0 and 1.2"). I also cleaned it up and lubed it with some WD. When I had it up on a jack I noticed the same noise as I did yesterday, I don't think it's a problem. I just noticed it more because the bike was going a lot faster, and I didn't have my helmet on at the time.

Thanks again for all the help guys.

[Alex]

Did you use any chain lube other than WD? WD works OK for cleaning the thing, but it's only marginally effective as a lube, and then only if you re-apply it on pretty much every ride.

[Red'09250]

I just used WD, but I picked up some chain lube today (Gunk liquid wrench chain lube). I'll lube it up after my next ride so the chain's nice and warm.

[kkim]

I'd highly suggest Maxima Chain Wax if you're looking to buy some chain lube anyway.

[Banzai]

Since you said that you have the tension set correctly, especially if you're not used to adjusting things on bikes, sometimes you'll notice a little noise if the rear tire/sprocket isn't pretty much perfectly aligned. THE NOCTCHES ON THE ALIGNMENT TABS ARE A QUICK REFERENCE ONLY, and by no means perfect or should they be the primary source of measuring if you got the alignment correct. Even if you turned the adjustment nuts the same number of turns, you still may not have the same alignment that you had, although it will be close.

If what you're hearing is something that sounds a little like a gear whine and it's vehicle speed related, it's a sure bet that it's a sprocket alignment issue. Only takes about 1/4 turn difference to make the noise. Most considder it normal, but it will cause the chain and rear sprocket to wear faster. It shouldn't be enough to worry about, really, but some who are really tuned into their machines claim they can also feel the rear tire getting a little squirley, too. With as little contact patch as we have with the 130 rear tires, every little detail helps.

Old school method of aligning the sprockets/rear tire was to use a straight edge on the face of the front and rear sprocket. Turn the adjuster on the sprocket/chain side to get proper tension, and then turn the off side one to get alignment, recheck tension adjustment, tighten all bolts/nuts, and ride happy. It's more work, but ensures a proper set up every time.

I'll take a picture of the tool that I made to check and post it as soon as I can. Basically, it's a piece of 1/2 inch steel electrical conduit tubing with two pointers on it so I can measure from the center of the swing arm bolt to the center of the rear axle bolt. Easily gets it spot on every time.

[Red'09250]

Yeah, I noticed that the adjustment tabs couldn't be perfect because I caught them actually moving around a little bit once I had loosened the axle nut. I put them both as far forward as I could figuring that if they're off the exact same amount then the alignment tabs would be the most accurate.

A picture of some kind of device that would make this easier would be great. I can imagine wheel alignment being pretty important when you get up to higher speeds.

Some kind of tool for measuring chain slack would be great too. I don't think my "hold a piece of paper held next to the chain" method is very accurate.

[Banzai]

Originally Posted by Red'09250

Some kind of tool for measuring chain slack would be great too. I don't think my "hold a piece of paper held next to the chain" method is very accurate.

I'll post a pic of one of those, too! Probably should go into the Wiki, too! A picture is worth a thousand (sometimes curse) words!

[Banzai]

This is a Chain Tension Gauge.
Materials: Scrap piece of wood, dowel rod, tape, and piece of paper.

Cut scrap wood as a base to any size you're comfortable with. Drill hole in base to fit dowel rod. Glue dowel rod into hole. Trim dowel rod so that overall height of tool is approximately 11-12 inches (start long, trim to fit depending on if you have a rear stand or use blocks under your kick stand). Cut piece of paper approximately 4 inches long by 2 inches wide. Mark a red line down the center of the 4 inch length. Make a line 10mm and 15mm above and below the center line. Wrap the dowel rod with masking tape STICKY SIDE OUT. Stick the paper onto the tape.

To use: Level your bike, either with blocks under the kickstand or raise the rear with your swingarm stand. Place the gauge under the chain. Adjust the paper (if you did it right, it should slide but remain where you put it) so that the red line is flush with the visual bottom (or top, whichever you prefer, just use the same point for every measurement) of the chain. Spin tire to get chain slack where you want to measure it (manual says where it's tightest), and pull down and push up on chain. If the bottom of the chain moves LESS than the 20mm mark, it's too tight. If it moves MORE than the 30mm mark, it's too loose. Play with the gauge to get the feel for how it works. Adjust tension and check it again. Once you do it once, you'll figure it out!

The two lines closest to the center (inner set) are MAXIMUM tight chain tension of 20mm and the lines furthest out are MINIMUM chain tension of 30mm.

[Banzai]

This is the Wheel Alignment Tool



Materials: 24 inch length of 1/2 inch electrical conduit, 2 1/2 inch ground clamps, 2 1/4x20 nuts, 1 12 inch length of 1/4x20 threaded rod cut in half with two ends ground to a point.

Tighten one of the clamps to the end of the conduit. This end should NEVER move, as it's your reference point. Loosely attach the other clamp to the other end. Cut the 12 inch threaded rod in half. Grind one end of each 6 inch piece to a point. Secure each rod half into the ground screw of the clamp and tighten the jam nut securely.

To use: First, remove the little plastic plugs that cover the swingarm bolt (they just pull out) and use a sharpie to mark a dot in the center of the bolt on BOTH sides. It's easier than it sounds, and as long as you get it halfway right you'll be OK (I promise!). Make a dot in the center of the axle bolt in the same manner (you'll have to do it when the cotter pin is out or bend it out of the way).

Once you have PROPERLY set the chain tension with the Chain Tension Gauge, check the measurement on CHAIN SIDE and set your gauge. Put the NON MOVING side point on the dot on the SWINGARM bolt and adjust the other clamp/point to the center of the AXLE bolt. Tighten your gauge screws carefully by hand at first, then with a screwdriver. Recheck and adjust if necessary.

Now, take your gauge to the muffler side. The NON MOVING pointer MUST remain indicating on the SWINGARM bolt!!!!!! Check your alignment on the muffler side by again checking swingarm bolt center to axle center. DO NOT ADJUST THE GAUGE, turn the alignment adjuster nut on the MUFFLER SIDE ONLY to adjust alignment.

Recheck that both sides read the same BEFORE and AFTER torquing axle nut and adjuster nuts to proper spec.

[Banzai]

Adjust chain tension.
Adjust wheel alignment.
Recheck chain tension.
Adjust wheen alignment and chain tension as many times as necessary to bring within spec.
Torque all fasteners to spec as per the service manual.
Recheck chain tension and wheel alignment.
Insert cotter pin into axle and reinstall swingarm bolt covers in frame.
Ride happy!

[Red'09250]

Awesome man, thanks for the pic. I'll see if I can come up with something similar.

I was thinking of making a bobweight to hang from somewhere behind the chain with a similar paper on it, but I don't know where I'd hang it from so that it's not rubbing against the chain.

I went for a quick ride today and noticed a high pitched whine coming from the bike. It got higher pitched the faster I went. I stopped and checked out the chain and rear sprocket, didn't see any wear at all on either, so I continued the ride. I didn't notice any roughness or vibrations and went up to 65mph. I'll keep an eye on the chain/sprocket, but I don't think they're too terribly out of alignment.

Thanks for all the replies guys, you've all been really helpful with this!

[Banzai]

Originally Posted by Red'09250

Awesome man, thanks for the pic. I'll see if I can come up with something similar.

I was thinking of making a bobweight to hang from somewhere behind the chain with a similar paper on it, but I don't know where I'd hang it from so that it's not rubbing against the chain.

I went for a quick ride today and noticed a high pitched whine coming from the bike. It got higher pitched the faster I went. I stopped and checked out the chain and rear sprocket, didn't see any wear at all on either, so I continued the ride. I didn't notice any roughness or vibrations and went up to 65mph. I'll keep an eye on the chain/sprocket, but I don't think they're too terribly out of alignment.

Thanks for all the replies guys, you've all been really helpful with this!

Yup, that whine coming after a chain adjustment is surely just that, wheel alignment. Seen it a million times. Just a little off won't hurt short term, but if you keep it long term it WILL wear the rear sprocket uneven and hurt the overall life of the rear sprocket and chain.

Ask me how I know!

[Red'09250]

haha, ok, point taken. i'll take it into the dealer in a few days to have it looked at. i don't have time to work on it during the week (was hoping this would be a quick weekend thing, yeah right).

thanks again for all the advice

[Banzai]

Originally Posted by Red'09250

haha, ok, point taken. i'll take it into the dealer in a few days to have it looked at. i don't have time to work on it during the week (was hoping this would be a quick weekend thing, yeah right).

thanks again for all the advice

No real need to take it to the dealer to have it done and spend money if you're not going to put too many miles on it and will have time later to set it up right. If you know enough about it to have done the initial tensioning that got you into having your noise, you know enough to fix it! You can do the same alignment thing with a standard 36 inch metal ruler and two pencils! Just tape the pencils to the ruler and you have basically the same thing as the gauge I made!

Never, my friend, NEVER pass up the opportunity to buy or make new tools!

[kkim]

http://faq.ninja250.org/wiki/How_do_...l_alignment%3F

[Banzai]

Originally Posted by kkim

http://faq.ninja250.org/wiki/How_do_...l_alignment%3F

Cool deal, seems there's nothing new under the sun.

I copied my tools from ones that I saw in a shop some years ago, although that old timer had a purpose built straight edge and a highly calibrated eyeball!

[Red'09250]

lol, thanks guys. i'll give this another shot when i get some free time this week

thanks again for all the help!

[Red'09250]

well, i actually had a very light day at work today. so i stopped by lowes and picked up all the crap i'd need to make this tool. i threw it all together, measured the distance from the two nuts (yes they were slightly out of alignment), and adjusted them back to equal distances.

The sight meters are about 1 whole notch off! I haven't had the chance to take it for a ride yet (maybe after dinner), but I'm pretty confident it'll be nicely aligned.

[Red'09250]

A quick ride confirms it, the tire is in alignment. At least as far as I can tell. I rode with no earplugs and didn't notice the whirring noise.

Thanks guys, problem solved.

[Banzai]

Originally Posted by Red'09250

A quick ride confirms it, the tire is in alignment. At least as far as I can tell. I rode with no earplugs and didn't notice the whirring noise.

Thanks guys, problem solved.