Are You Sick Of You Bolts Snapping!!!!

kla63 · #1 (**permalink**) 09-15-2009, 09:27 PM

got sick of my rear bolts breaking!!!!!!!!so i retap them to a nice 5/16s bolt, plus i made a rear mount support underneath so the engine will not move or vibrate came out sweet 500miles since upgrde and holding strong!!!!!!!!

,

Retmachinist · #2 (**permalink**) 09-15-2009, 11:38 PM

Quote:

Originally Posted by kla63

got sick of my rear bolts breaking!!!!!!!!so i retap them to a nice 5/16s bolt, plus i made a rear mount support underneath so the engine will not move or vibrate came out sweet 500miles since upgrde and holding strong!!!!!!!!

,

I had one motor that had the same issue. Pulled it off and re drilled and tapped the back holes to 5/16-18. Then I used grade 8 SHCS. I even used a lock wire on the heads so they cannot back out.
That motor vibrates more than any of my other ones. I am wondering what will be the next bolt to break or fall out. I love these things, they keep me busy, and out of trouble.

John

azbill · #3 (**permalink**) 09-16-2009, 05:58 PM

can we get pics of your mount/support ???
enquiring minds want to know !

impression · #4 (**permalink**) 09-17-2009, 03:20 AM

need to get crank balanced

i plan to get this done on mine

city of angels · #5 (**permalink**) 09-17-2009, 04:16 AM

u could also use the kit that usabikemotors sell it comes with all the hardware you need to upgrade i just got my motor back from the shop and it comes with grade 12 bolts allen heads and so far everything its tight as whistle thewhole kits sell for 28.00 plus tax

omegaunderground · #6 (**permalink**) 09-17-2009, 05:01 AM

I saw an engine bolt upgrade kit on sickbikeparts for 10$ It will make all your bolts into allen bolts, I am sick of stripping out those Phillips bolts!

city of angels · #7 (**permalink**) 09-17-2009, 10:16 AM

if read the descriptiion on sbp thse are grade 5 the ones for uabikemotors are grade 12 i rather be save than sorry i dont want to go down a hill a bolts snapping that why i rather use grade 12

impression · #8 (**permalink**) 09-17-2009, 11:41 AM

apparently while strong grade 12 bolts have the flexibility of glass, so once they go over their threshhold they snap like tqigs as they have no 'give'

AaronF · #9 (**permalink**) 09-17-2009, 02:56 PM

My mounting is holding right now with stock M6 bolts,do you think it would be worth drilling it out an tap to a standard size?Its nice to know i can ride the bike anywhere in town without the grade 2 bolts breaking but I'd feel safer with some grade 8 bolts.What do you think is it worth it?

Brvnkaerv · #10 (**permalink**) 09-17-2009, 04:59 PM

I must be behind the times. I thought grade 8 was the top. and the newest innovation. I know that there are grade 9 lifting chains available. The best bolts I have ever used were standard alloy steel cap-screws fom a manufacturer named "Holo-Chrome". Brvnkaerv