Db30 predator 6.5 upgrade


New Member
Sorry for the dumb questions that I am about to ask. I have tried searching but still have questions. I appreciate any time that you can spend helping. Thank you.

Ordering the Harbor freight engine. #60363 and #69730 are the same price. Is the HEMI any better? Why pick one over the other?

I am going to get a new clutch and chain. Figured i would go with the 3/4 #40 chain. will that work with the sprocket on the rear wheel? Anything else I should concern myself with?

Will the bolt holes match up for mounting the engine? Do i need to drill out new holes?

I see some info on a throttle linkage kit for the predator (https://www.OldMiniBikes.com/predator-212cc-mini-bike-amp-go-kart-throttle-linkage.html). Is this needed? I am not great at fabricating, FYI.

Any other considerations I should take into account? What about chain tensioner, is there a better solution then the one on the bike?

Thank you all in advance!!


New Member
Also, I have seen after the swap that people have the clutch on backwards. I assume it is to line up the chain. How is that done? Is it always needed?
Greetings..get the hemi because has a better valve rocker setup and for sure a flat top piston..the clutch needs to be reversed to line up the chain.i just look at rear of bike with chain on and move the engine back and forth to see if it's straight use a stright edge to check if needed...take a scribe or paint on a q-tip to mark holes to drill plate..for the kill switch just take one of the wires apart at oil sensor and put wires to switch between then to interrupt circuit..good luck
What he said but the rear DB sprocket is #35 chain so get a Max-Torque 12th clutch and if you can afford it buy RLV Gold on Gold chain it's the best and worth the cost IMO .


New Member
So i will line up the new HEMI engine, drill out the new holes so that the inboard clutch (max-torque 12t) will be in a straight line with the rear sprocket. Adding a new gold/gold chain.

No need to a throttle linkage, right? Anything else missing?
Loosen linkage nut to free stiff stock lever because was built to stay put..get a spring to make it return..you will see what i mean ounce you loosen the nut on throttle plate..:p


New Member
Is this type of thing needed, or can i go straight to the Predator engine? I will no be removing the governor at this time. Thanks.
ok. The update:

I got the HEMI 6.5 from HF for 99$. I got a new chain, Max-Torque clutch and a clutch guard form www.OldMiniBikes.com, The install was not hard. Drilled new holes in the plate (had to make them long to fine tune the chain tightness) and install the clutch. Needed to run to Ace for some new grade 5 bolts for the engine and we were done.

My 100lbs son jumped on it and hit the throttle and the front wheel jumped off the ground. They have been running around on it ever since. It goes about 40 mph, but the incredible part is how quick it gets to speed.

Next plans... Maybe a new exhaust and air-filter. I see no need to remove the governor as it is running great as it is. This was a great upgrade