New Engine Questions

micromaster22

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Jul 14, 2017
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Just bought a new 80cc engine online. Bought it from ebay, its a basic 80cc/66cc (Jet) engine. Ill post a link to the engine on ebay. I Was wondering if you guys have any tips for me regarding break in or assembly. I was thinking about breaking in with Opti2 at 100:1 but open to suggestions. Also, how much assembly is required? Loctite? Replace bolts? Thanks in advance guys!

http://www.ebay.com/itm/162126187665
 

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crassius

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pic is of the older style motors - many folks are tempted to put loctite on a lot of the fittings for these, but I never recommend that for anything on these kits - nuts will come loose a bit, but that is because the bolts are stretching rather than nuts spinning out

handled carefully and adjusted often when new, these kits work fine, and need nothing but care and maybe some PVC in at least the rear mount
 

micromaster22

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pic is of the older style motors - many folks are tempted to put loctite on a lot of the fittings for these, but I never recommend that for anything on these kits - nuts will come loose a bit, but that is because the bolts are stretching rather than nuts spinning out

handled carefully and adjusted often when new, these kits work fine, and need nothing but care and maybe some PVC in at least the rear mount
when you say pvc for the rear mount do you mean a piece of pvc cut in half to hug the downtube on the bike to make a flusher fit? I am also using sickbikeparts front mount.
 

FurryOnTheInside

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I have one of the older style engines that I got on eBay, it's all that is available in Europe as far as I can find. I'm trying to follow all the tips and tricks shared in the newbie threads here, including replacing the cheese grade hardware right at the beginning, and Jaguar's advice on vibration reduction. Idk if it's enough to make it a decent engine but it is as much as I can do. I cba to buy special oil just for break in so I hope that it's okay using the synthetic oil at 24:1, I expect that it'll be fine.
 

micromaster22

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I have one of the older style engines that I got on eBay, it's all that is available in Europe as far as I can find. I'm trying to follow all the tips and tricks shared in the newbie threads here, including replacing the cheese grade hardware right at the beginning, and Jaguar's advice on vibration reduction. Idk if it's enough to make it a decent engine but it is as much as I can do. I cba to buy special oil just for break in so I hope that it's okay using the synthetic oil at 24:1, I expect that it'll be fine.
Do you happen to know the sizes for replacement bolts? Also what is Jaguars advice on vibration reduction?
 

FurryOnTheInside

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Do you happen to know the sizes for replacement bolts? Also what is Jaguars advice on vibration reduction?
Well you have to take them out to replace them, so rather than rely on my on-the-spot memory... ! ;)

Well, again I don't suggest that you trust me, but read the forum and dig up the info yourself to get the full background and make these judgements for yourself. The background info means more than anyone can possibly put into their replies in this thread.
https://motoredbikes.com/threads/cheap-easy-power-mods-suggestions.48110/#post-417266


Definitely read all the newbie threads for a start, and then dig into all the various topics and the older threads if your engine is on the primitive side.
Let me see if I can find a link to get you started on Jaguar's tips...
Ah, this! Lots of reading and all of it useful even if not all relevant to your build
http://www.dragonfly75.com/motorbike/
 
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crassius

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yes, PVC at rear mount is important - a piece cut in half (or sometimes a third for skinny tubes)

mounting studs are 6mmx1.0, grade 4.8 and could be replaced by a better grade of steel like 8.8, but will work OK as they are if you use care with them
 

micromaster22

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yes, PVC at rear mount is important - a piece cut in half (or sometimes a third for skinny tubes)

mounting studs are 6mmx1.0, grade 4.8 and could be replaced by a better grade of steel like 8.8, but will work OK as they are if you use care with them
Random question that you might not know the answer to, Sick Bike Parts front engine mount came with some black allen head bolts that threaded perfectly into the front engine mount holes. Are the front and rear engine mount bolts both 6mmx1.0? Ive seen other websites and posts say m6x1.0 , is this the same size? Also should I loctite the engine mount bolts? Thanks for your help here. Awesome forum!
 

crassius

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yes, same size - newer motors use m8x1.25 to eliminate most mounting problems (in US, we're not used to metric, so pardon us if we list it strangely)

I never have, and never will use loctite on anything in these kits - problem is not nuts loosening, but rather bolts stretching. Also, too many adjustments to make and things that may need to come off and go back on again.

I'm not a builder, just a repair shop and if you loctite everything, you'll pay a LOT more in labor time for me to fix it.
 

micromaster22

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yes, same size - newer motors use m8x1.25 to eliminate most mounting problems (in US, we're not used to metric, so pardon us if we list it strangely)

I never have, and never will use loctite on anything in these kits - problem is not nuts loosening, but rather bolts stretching. Also, too many adjustments to make and things that may need to come off and go back on again.

I'm not a builder, just a repair shop and if you loctite everything, you'll pay a LOT more in labor time for me to fix it.
Thanks for the tip. Last question, how much assembly is required ? I know you dont know personally with this seller but i heard most engines and kits come disassembled.
 
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