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Sprocket Bolts

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I have having problems keeping my sprocket bolts tight on my 04 CRF 450. I have put new one's and they break and get loose. I finally put some lock washers behind the lock nut on my last ride and it seemed to help some.

My buddy boy down in Louisiana was in a race on a CRF250 and his bolts broke off a big jump and he was hurt really bad. The hole back wheel came apart.

Is anyone else having this same problem????? 😢

I have been racing for a very long time and never had this problem before.

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Use Yamaha nuts and bolts. They are not bad to work loose and the bolts are real strong.

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I have tried the Yamaha Bolts and nuts. I have used red locktite.

Does anyone think the threads could be streching on the bolts?

I have broken off bolts while riding!! even after making sure they are tight before riding!!! I have never had this problem with any of my other bikes.

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Check the holes on the hub and sprocket too. If they're outta round, that'll allow the bolt to move (under load), thus causing problems.

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Somewhere I read that you need to put loctite on the bolt threads plus where the bolt head recesses into the sprocket.

This is how I reassembled mine, I'll check tonight to see if any have gotten loose.

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You know that is just odd that some people have troubles with these things...my 2003 is on the original bolts and nuts...I went through the stocker sprocket, a Renthal, and I am now on my second Ironman....4 sprockets! The bolts have never come loose....I use blue loctite on them. That's it.

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I second that TR but I've never used locktite and nothing has happened!!

BTW, thanks for changing the Avatar!!!

Don 😢

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I second that TR but I've never used locktite and nothing has happened!!

BTW, thanks for changing the Avatar!!!

Don 😢

You may want to rethink this....that is how many I know have ended up on their head with shattered hub and damage to swingarm/sprockets - a little insurance with loctite will lessen that chance - I believe it is well worth the peace of mind! 😢

Interesting - almost everyone I know who rides any 450(Red, Blue or Orange) had issues with loose bolts eventually, until they learned the proper way to use loctite - torque the nuts correctly with counter force on the bolt side - (otherwise it spins)

you must let the loctite set up for 24-48hrs before riding and if you ever tighten the bolt or nut, after it sets up - you have broken the seal - make sure you replace any stretched bolts 😢

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Not being a wise-ass or so, but I've used just the original nuts/bolts since I got my '03 and now its almost 2 yrs old (had the original aluminum rear, then a Moose SS, then an Ironman) with no problems. Being an Engineer myself, I believe if you follow the tightening process per the manual and torque specs you should have no problems (and of course periodic checking of tightness helps too). Just my $.02.

Don 😢

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I destroyed 2 rear hubs with this problem a couple of years ago. Another buddy did the same. Here is what we came up with and no failures since.

Once the bolt becomes loose it and takes a few twist of the throttle it becomes fatiuged. You will never get it to stay tight because it will stretch easier and easier. If you over torq the bolt the same will happen.

So once they become loose you need to replace them.

With the new ones I use Locktite and the proper torq specs.

No problems since. Good luck.

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Your bolts may or may not be coming loose from over or under torquing them, but at least you can rule that factor out with some careful work. If you're using a torque wrench on the bolts, make sure the threads are not lubricated if you are torquing them to spec, or take the reduced friction into account when tighting them. While a general guideline is to reduce torque by ~20% with lubricated fasteners, specifics depend on a number of different factors. The ideal torque for a bolt is ~50% to ~60% of it's elastic limit, which is area where nuts and bolts tend to stay together. Over torquing a bolt past the elastic limit puts it into the yield zone, which happens when the piece you're tightening up becomes easier to turn. Once you're in the yield zone, the bolt will stay stretched and must be replaced.

On new bolt applications, the friction factor changes with each use up to a point. For instance, the first time you torque a fastner, the friction will be at its highest. The second time you torque a fastener to spec, it's friction will be reduced and so on up until three to five cycles and from there it becomes constant. There's a pretty significant reduction in friction from the first to the second cycle, but it's much smaller afterwards. My advice for critical applications would be to torque the 'new' bolt to spec, then slightly loosen it and torque it again. Cycling it five times like this before your final torquing will insure the friction is leveled out.

If you're using a clicker type of torque wrench and you keep it stored at a value greater than zero force, it will loose its calibration over time and you'll need to take that into consideration. Always store a clicker type torque wrench without any preload to help maintain it's calibration. Ideally for accuracy, you want to be using a torque wrench that matches the application within the most accurate range of the wrench, which will be in the meat of its torque range. For instance, you would not want to use a 1/2" clicker type torque wrench that has a torque range of 0 to 200 ft/lbs to torque a 1/4" fastener to 5 ft/lbs. A better and more accurate option would be to use a smaller torque wrench with a range of 0 to 10 ft/lbs.

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The three most common types of torque wrenches are the beam type, the clicker type and the dial types. The beam type torque wrenches are good for general purpose work, but accurate reading of the indicator is difficult at various angles unless you’re looking directly on the pointer. These are often the least accurate types of torque wrenches.

The micrometer or click type of torque wrench varies in accuracy depending on the manufacturer & model. Some can be as accurate as +/- 3% or more. One of the downsides to these types of wrenches is that the release point can sometimes be difficult to manage without over tightening a fastener. Another downside is that this type of torque wrench does not measure actual torque in real time or rolling torque.

The dial type of torque wrench is often the most accurate of these types and is my personal favorite. Some can be as accurate as +/- 1% or better, but this varies by brand / model and 2% accuracy is more common in the higher end wrenches. The downside with this type of wrench is being able to accurately read its dial in some positions unless you’re looking square at the dial. This type of wrench gives you accurate real time torque while tightening. It will also allow you to read rolling torque (pinion bearings, etc).

A good torque wrench will usually come with a graded torque sheet that shows exactly how accurate it is at various increments throughout its torque range. I’m partial to the Proto brand for most of my torque wrenches, torque screwdrivers, etc, but some of the other companies offering high quality torque wrenches are Proto, SnapOn, Mac, SK, Matco, Armstrong, CDI, etc. In the last several years, advances in technology, production, etc, have allowed the prices of accurate digital torque wrenches to come down in price, which is where the future is headed.

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hey Rex you might tell tinman about the bolts problem, I just lace a wheel for him on his 04 with a new hub and he's having the same problem keeping his sprocket tight 😢

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