Boom Vader 125 lower engine mount bolt

[vader125]

Boom Vader 125 lower engine mount bolt keeps breaking I've changed it out twice already, the stock one broke, then I bought a grade 8.8 bolt and it broke in less than a week, then I bought a grade 10.9 bolt and it broke in a couple weeks, I do have another grade 10.9 bolt, the thing is I would like to get a stronger bolt maybe a grade 12.9 bolt, What bolt would work the best? Thanks

[4T_Goblin]

Grade 8, not metric 8.8, but grade 8 standard

[vader125]

Originally Posted by 4T_Goblin

Grade 8, not metric 8.8, but grade 8 standard

Thanks, that’s what I was thinking, do you know if this one would work?

Dorman - Pik-a-Nut Cap Screw-Hex Head-Grade 8- 5/16-18 x 5 In.
https://shop.advanceautoparts.com/p/...E&gclsrc=aw.ds

[CheapThrills]

Broke mine too, even though I ensured the chain wasn't too tight.


Replaced it with better quality bolts: https://mymotorcycleblog.com/boom-va...olts-replaced/


Then figured it was time to upgrade the bolt sizes by drilling out the engine mount holes:
https://mymotorcycleblog.com/boom-va...olts-upgraded/


Going with larger bolts made the bike feel more solid to me, with less vibrations.


Just what I did, and liked it.

[vader125]

Originally Posted by CheapThrills

Broke mine too, even though I ensured the chain wasn't too tight.


Replaced it with better quality bolts: https://mymotorcycleblog.com/boom-va...olts-replaced/


Then figured it was time to upgrade the bolt sizes by drilling out the engine mount holes:
https://mymotorcycleblog.com/boom-va...olts-upgraded/


Going with larger bolts made the bike feel more solid to me, with less vibrations.


Just what I did, and liked it.

Nice thanks for that update how to put even bigger bolts.. for now I used the 5/16-18 grade 8 bolt and so far so good we’ll see…

[4T_Goblin]

You do not need to drill anything. You want as much metal to screw to as possible. Those are mount holes are already small enough. Just get the grade 8 5/16" about 4.5 to 5 inches long and some washers until you add a third mount

[vader125]

Originally Posted by 4T_Goblin

You do not need to drill anything. You want as much metal to screw to as possible. Those are mount holes are already small enough. Just get the grade 8 5/16" about 4.5 to 5 inches long and some washers until you add a third mount

Already bought that bolt and put it on with some thread lock, it looks stronger for sure, what third engine mount do you recommend and is it really necessary?

[Deckard_Cain]

Originally Posted by vader125

Already bought that bolt and put it on with some thread lock, it looks stronger for sure, what third engine mount do you recommend and is it really necessary?

For the WHAT: You aren't going to find one commercially made, it's going to need to be done by you or someone else. Typically they are welded to the swingarm tube of the frame, then bolted to either 2 or all 4 lower engine mount bosses that are already there.

I'm working on making one for my 190 swapped Vader this spring, but I plan on mine being removable and bolting to the frame instead- especially since I'm going 212cc with 4v head and the extra power and torque will be nasty.

For the WHY/Is it necessary: One could successfully argue that it should have been there from the factory. Same story with the actual Honda Grom... for those, you can buy the extra lower mount but they don't exactly fit onto the clones.

So basically, I'd say yes, it is necessary. Even on a bone stock engine, it'll take all of the vibrations out and smooth it over nicely, make the bike feel more solid when the engine is running. On any kind of modded engine, 141cc kit, or better... absolutely in my experience and opinion,

[4T_Goblin]

There are third motor mounts available but as Deckard explained they will have to milled out to fit the clone, or you will need to make your own.

I do not have a third mount on mine yet

[vader125]

Originally Posted by Deckard_Cain

For the WHAT: You aren't going to find one commercially made, it's going to need to be done by you or someone else. Typically they are welded to the swingarm tube of the frame, then bolted to either 2 or all 4 lower engine mount bosses that are already there.

I'm working on making one for my 190 swapped Vader this spring, but I plan on mine being removable and bolting to the frame instead- especially since I'm going 212cc with 4v head and the extra power and torque will be nasty.

For the WHY/Is it necessary: One could successfully argue that it should have been there from the factory. Same story with the actual Honda Grom... for those, you can buy the extra lower mount but they don't exactly fit onto the clones.

So basically, I'd say yes, it is necessary. Even on a bone stock engine, it'll take all of the vibrations out and smooth it over nicely, make the bike feel more solid when the engine is running. On any kind of modded engine, 141cc kit, or better... absolutely in my experience and opinion,

Thanks for the break down, it seems like it will make it better for sure, I’ll probably do it once I get around to it since it needs to be welded and not a direct bolt on. For now hopefully this grade 8 bolt holds up.

[vader125]

Originally Posted by 4T_Goblin

There are third motor mounts available but as Deckard explained they will have to milled out to fit the clone, or you will need to make your own.

I do not have a third mount on mine yet

I’ll have to wait to do that one since it isn’t a direct bolt on, seems like it would make a noticeable difference.