2 STROKE WORLD .net

The 2-Stroke Garage => Turning Wrenches => Topic started by: Striker1423 on October 21, 2019, 08:12:53 AM

Title: Bolts vibrating loose
Post by: Striker1423 on October 21, 2019, 08:12:53 AM
So I know these RD's aren't the smoothest running bikes ever but is it normal for them to vibrate the front motor mount bolts loose periodically? Lol cause it just did it yesterday. I heard this weird rattling squeelingnkinda noise. I look down and I see a bolt spinning itself right out of the motor at 55. I pull over and  it's the front lower motor mount bolt. Obviously the nut was long gone.

I grabbed it and rode with it in my hand a fewmkioes to TSC and got some unlock nuts to put it back together. But it was kinda weird.

Also, anyone ever experience a semi loud whirring noise after installing a vape system? Runs just fine, but in her this high pitched whir when I move my leg to the side and bend down to listen. The magnets can't be touching the ststor cause it would break it right? Perhaps the plastic insert that covers them is rubbing slightly?

Title: Re: Bolts vibrating loose
Post by: Striker1423 on October 21, 2019, 08:15:04 AM
Double post. Stupid smartphones.
Title: Re: Bolts vibrating loose
Post by: m in sc on October 21, 2019, 08:27:36 AM
yes. the stock long bolts, well, they can stretch and the nuts come loose. worst case is the bolt hammers and breaks the mount, or frame tube. have had both happen.

I use individual (shorter) bolts at each of the 4 points with nylock nuts. use allen bolts, head inside toward motor, nuts out. 

nuts out. (:dawg:)


But seriously, this works.  :twocents:
Title: Re: Bolts vibrating loose
Post by: Jessup on October 21, 2019, 11:56:48 AM
Wedge-locking washers :thumbs:

(https://kk.org/cooltools/files/2016/11/nord-lock.jpg)
Title: Re: Bolts vibrating loose
Post by: m in sc on October 21, 2019, 12:01:31 PM
^ those are fantastic as well.  :clap:
Title: Re: Bolts vibrating loose
Post by: rodneya on October 22, 2019, 12:03:57 AM
Quote from: Striker1423 on October 21, 2019, 08:12:53 AM
So I know these RD's aren't the smoothest running bikes ever but is it normal for them to vibrate the front motor mount bolts loose periodically? Lol cause it just did it yesterday. I heard this weird rattling squeelingnkinda noise. I look down and I see a bolt spinning itself right out of the motor at 55. I pull over and  it's the front lower motor mount bolt. Obviously the nut was long gone.

I grabbed it and rode with it in my hand a fewmkioes to TSC and got some unlock nuts to put it back together. But it was kinda weird.

Also, anyone ever experience a semi loud whirring noise after installing a vape system? Runs just fine, but in her this high pitched whir when I move my leg to the side and bend down to listen. The magnets can't be touching the ststor cause it would break it right? Perhaps the plastic insert that covers them is rubbing slightly?


I had something stock to the magnets when I was fitting mine and it made weird noise when I spun the flywheel.
Maybe check the pickup gap as well.
Title: Re: Bolts vibrating loose
Post by: quocle603 on October 22, 2019, 04:19:40 PM
Quote from: Jessup on October 21, 2019, 11:56:48 AM
Wedge-locking washers :thumbs:

(https://kk.org/cooltools/files/2016/11/nord-lock.jpg)

Wish those things weren't so expensive.
Title: Re: Bolts vibrating loose
Post by: RSW46 on October 23, 2019, 05:46:00 AM
The Wedge type lock washer work well with Nord-lock being the best known. They are thicker than the standard spring lock washer and you would need one under the bolt head as well as the nut to work well. The standard bolt may not be long enough to put two of these on. There is another knock of version of these wedge washers that are a little cheaper but also thicker than the Nord-lock. In my industry we would only use them once; if the joint had to be broken then the lock washer would be replaced. The last bit would apply to all types of lock washers, which I do not always follow on my personal projects.

Amazon sell them in small quantities.
https://www.amazon.com/Wedge-Locking-Washer-Carbon-Coated/dp/B007VAW4FG/ref=pd_bxgy_328_3/145-9502586-3487521?_encoding=UTF8&pd_rd_i=B007VAW4FG&pd_rd_r=8220ab11-dbe8-4765-82e7-817c0657b13e&pd_rd_w=rX8AS&pd_rd_wg=r80Tz&pf_rd_p=09627863-9889-4290-b90a-5e9f86682449&pf_rd_r=PMTMQ0PA5T8G8XM2K5K2&psc=1&refRID=PMTMQ0PA5T8G8XM2K5K2
Title: Re: Bolts vibrating loose
Post by: Striker1423 on October 23, 2019, 08:32:10 AM
I've heard of norlock before. Might try those. Nylocks should work for now. Gonna take another look at the rotor to make sure it isn't rubbing somewhere. Good info fellas!
Title: Re: Bolts vibrating loose
Post by: m in sc on October 23, 2019, 09:57:00 AM
the nylocks and nordlocks will work. but the issue here is the bolts themselves do stretch. I mean, you can safety wire the nuts as well, or drill and use castellated nuts too.  :twocents:

Title: Re: Bolts vibrating loose
Post by: IR8D8R on October 25, 2019, 11:34:28 AM
Prevailing torque lock nuts. The kind used on aircraft. AKA crimped nuts. You've probably found them on auto exhaust manifolds.

They were the only thing that wouldn't vibrate off my enduro shifter kart without safety wire or green loctite.

They will cause wear to mild steel fastener threads if they are removed and replaced a lot.

Like nylocks they can't be hand tightened at all so they can be a PITA.

IR8D8R
Title: Re: Bolts vibrating loose
Post by: m in sc on October 25, 2019, 11:43:56 AM
https://www.mcmaster.com/94235a090

these work well as well. have them on my header on one of my cars.