Acorn nuts will destroy your engine

stevenflintrichards

stevenflintrichards

New Member
i am a noob to bike engines but to small engines i am not , i have over 15 yrs experiance but f*%$ me running them acorn nuts made the studs bottom out on my first engine pulling the threads right out of the block . some day when i am bored ill get a heli coil set and rebuild that engine and either sell it maybe build a bike and sell it or keep it as a back up or for parts
 
Problems with the pretty chrome acorn nuts that come on most engines is nothing new. They have caused builders a lot of problems, some of which go undetected until the head gaskets start leaking or blow completely. The problem seems to be an inconsistancy in stud length or how far the studs are threaded into the case. If the stud is not seated properly, or is too long, the acorn nut will not tighten sufficiently against the cylinder head to allow for a proper seal at the head gasket.

Many/most of us replace the acorn nuts with hex nuts torqued to the proper value for the stud diameter before ever starting the engine for the first time.
Some have never had a problem with the acorns but enough have that we always suggest to toss them, or use them for ballast.
Tom
 
Ummm, someone hasn't been reading the stickies!!! :>(
I replace all the studs with metric 8.8 (approximately a USS grade 5), use flat washers and locking nuts. I insert the studs to the bottom and back them out 1/8 to 1/4 turn. Not even good for a ballast, or fishing weight, but not bad in a sling shot.

Pre instillation of a HT
 
Last edited:
I install new studs and JB weld them into the block. If I use acorn nuts, they are decorative only over real nuts.
 
my father retired from Carlisle he was there chief quality control guy not regional but nationally , his thoughts are what if it seizes up for what ever reason , lets say your going down the road and it welds its self shut or wonder how many of these have caught on fire , my father being top dog on quality control for a company like that i think would know granted he moved to texas a few years back and im still here in sh*% flint michigan but he says the computers were using there china made our phones are made in china and the new scooters all over the market are from china , so on one hand having to buy any thing made in china sucks but its about one thing do the people making all the money off our hobby want us to have something safe do they want us to have something we could die because of the give 2 fu@#$ less ! i know my bike can go 40 mph but am i going to go over 25 on a opium smoker no cause when it breaks and throws me on the ground i want to both be alive and not a pariliplegic , having a gas bike is fun but when the reality of what were running sets in its kinda graphic brutal and disturbing . if the chineese can make laptops and our tvs and other things in a some what reasonable quality how come there farting engines out like this ?
 
i work for a real-estate company im working on becoming a relator but i am looking into going to school for engineering Kettering university is here in town and seems to be one of the top schools to go to for that , brain fart lmao out loud in general most people are comical like the guy today saying put a lawn mower moter in my bike , i told him yeah if i do that it will get no oil and seize i may only be 30 yrs old but **** back in the 30s and 40s even a 12 YR old would know that , i am some what sad that i run into people who think they can work on engines only to find out there using beer cans for gaskets mixing 2 smoker gas with any oil even 90 weight gear lube this city is full of drunks with wet brain who think having a truck and scrapping makes them a mechanic ....
sorry most of you have no clue what living here in flint is like i rode down-town today it was 89 deg had 2 beers at a bar people walked by asking if my bike was plugged in or charging another thought i put a model air-plane engine in it and yet wile i felt like just riding my bike pedalling some guy was like yo bike busted yo lemme look at it ha had my pistol on me i kinda wish his drunk crack smoking ass would had tried something but yeah people here in flint where they still make chevy trucks dont know **** about how mechanical things work
 
I bought a motor from BGF then ordered the bolt kits from sick bike parts. The 8mm head studs would not thread into the block and the holes were not 6mm. They were more like 7.5mm and the studs were threaded fine into the block and coarse for the acorn nuts. I had to tap out the holes to 8mm. Then when trying to thread in the 6mm bolts for the Pirate Cycles CNS intake they stuck out 3/8ths of an inch. The whole block needed the 6mm holes tapped to the bottom. I ground off an old 6mm tap to do this.
 
Wow steve! Did someone crap in your cheerios? Take it easy and tone it down a bit willya?

Crappin' all over the Chinese stuff, and your home town are one thing, but do ya' have to fingerpaint a mural with it too?
 
Last edited:
stevenflintrichards said:
i work for a real-estate company im working on becoming a relator but i am looking into going to school for engineering Kettering university is here in town and seems to be one of the top schools to go to for that , brain fart lmao out loud in general most people are comical like the guy today saying put a lawn mower moter in my bike , i told him yeah if i do that it will get no oil and seize i may only be 30 yrs old but **** back in the 30s and 40s even a 12 YR old would know that , i am some what sad that i run into people who think they can work on engines only to find out there using beer cans for gaskets mixing 2 smoker gas with any oil even 90 weight gear lube this city is full of drunks with wet brain who think having a truck and scrapping makes them a mechanic ....
sorry most of you have no clue what living here in flint is like i rode down-town today it was 89 deg had 2 beers at a bar people walked by asking if my bike was plugged in or charging another thought i put a model air-plane engine in it and yet wile i felt like just riding my bike pedalling some guy was like yo bike busted yo lemme look at it ha had my pistol on me i kinda wish his drunk crack smoking ass would had tried something but yeah people here in flint where they still make chevy trucks dont know **** about how mechanical things work
Click to expand...

You sound just like the ppl that you're complaining about. Are you realy old enough to drink beer?

Vertical shaft mower engines have been converted to horizontal and used in bikes very succesfully. Old school stuff from before we had kit engines. Anyone with imagination and good mechanical skills can easily do it. The mount flange on them makes an easy mount in a bike frame. There are several builds depicted here in the DIY section, way back. Do a search.
BTW, your posts are extremely hard to read without punctuation.
 
Acorn nuts cannot and will not hurt a thing. That said, how they are used/ installed has the possibility to do alot of damage, as do most all parts of these kits.
Know what you are doing and know no damage.
 
GearNut said:
Acorn nuts cannot and will not hurt a thing. That said, how they are used/ installed has the possibility to do alot of damage, as do most all parts of these kits.
Know what you are doing and know no damage.
Click to expand...
I completely agree. Nevertheless you have to understand who you are dealing with; people with little to no mechanical background or experience. You, and others like you, Gear, could make them work with no problem. It's the ones who have never picked up a wrench and wouldn't know what to do with it of they did that our advice is aimed at.
A builder who doesn't understand that the acorns can be tightened and not apply the proper pressure to the cylinder head are the ones who will suffer the consequences and who need to be warned about the potential for problems.
Replacing them with hex nuts is the easiest way for them to avoid the situation. Agreed?

Tom
 
2door said:
It's the ones who have never picked up a wrench and wouldn't know what to do with it of they did that our advice is aimed at.
A builder who doesn't understand that the acorns can be tightened and not apply the proper pressure to the cylinder head are the ones who will suffer the consequences and who need to be warned about the potential for problems.
Replacing them with hex nuts is the easiest way for them to avoid the situation. Agreed?

Tom
Click to expand...

Yes, I definitely agree with this.
 
............:D:)
Ice_Age_2_Wallpaper_11_800.jpg
 
wikki said:
Halo effect

Ad hominem arguments work via the halo effect, a human cognitive bias in which the perception of one trait is influenced by the perception of an unrelated trait, e.g. treating an attractive person as more intelligent or more honest. People tend to see others as tending to all good or tending to all bad. Thus, if you can attribute a bad trait to your opponent, others will tend to doubt the quality of their arguments, even if the bad trait is irrelevant to the arguments
Click to expand...

once i read anything ad hominem, i stop reading.
 
This all boils down to taking responsibility into your own greasy hands. Yes I could go on and on and on and on and on and on like others (and not use any punctuation other than enough commas to put me in a coma) about how bad the chinese stuff is but I won't. :D

Bottom line is that if you ASSume these engines are without issues then you deserve what you get. But if you take your time and do some very simple blueprinting then you'll be rewarded.

My job is building V-Twin engines (think Harley) and I feel like a combination watchmaker and blacksmith as seldom does anything fit the way you'd expect it (or the way it should). American big twin bikes are nothing like working on cars where you can be pretty sure that stuff will fit right out of the box.

Checking the length of stud ends and the depth of the holes is SOP for me. I chase threads, blow them out with air, wash them with acetone and if using a threadlocker I allow it to set up overnight before applying torque. Yes, I'm the anal version of Felix Unger (you graybeards should get that reference LOL)
 
uniblab said:
Bottom line is that if you ASSume these engines are without issues then you deserve what you get. But if you take your time and do some very simple blueprinting then you'll be rewarded.
Click to expand...
This is well said lol.

uniblab said:
Checking the length of stud ends and the depth of the holes is SOP for me. I chase threads, blow them out with air, wash them with acetone and if using a threadlocker I allow it to set up overnight before applying torque. Yes, I'm the anal version of Felix Unger (you graybeards should get that reference LOL)
Click to expand...
When I did say old Ford F150 type water pumps There was always a couple of bolts that would be rusted quit a bit. I could never put them back in rusty per say as I would not get a proper torque reading from the bolt when putting it back in. So I would go to the wire wheel at the bench grinder and buff the threads clean.

Guess it depends on the type brand locktite? Because I have some stuff here that if it was allowed to set over night my torque reading would be like those rusty threads? Is what I am trying to say.

Used the stuff as a anaerobic sealer on intakes plenums you name it.. Good Stuff!

I do agree that it needs time to set up.
 
You must log in or register to reply here.
Back
Top