Honda ATV Forum banner

1 - 20 of 100 Posts

·
Registered
Joined
·
2,392 Posts
Discussion Starter #1

well dad and a friend got together and are starting my motor build not to bad but i wana c what yall think 97 300ex motor 395 bore sparks cam oversized valves hd spring kit 4 mm stroker crank 85 mm piston 400 carb hope to have it up and running by may will try to take pics for you guys during the build dad keeps pushing me out of the shop :icon_gd:
 

·
Super Moderator
Joined
·
18,227 Posts
How are you getting 395 bore out of a non-exhistant 85mm piston?

Who did your math?
 

·
Registered
Joined
·
2,735 Posts
^^^^^Exactly.Where did it go.And there is no 85mm piston for a 300ex.UUUGGGHHH!!
 

·
Super Moderator
Joined
·
18,227 Posts
Ok give him a break he's going to post progress pics.
I'll help him here is the first pic...
 

·
Registered
Joined
·
2,392 Posts
Discussion Starter #6

·
Premium Member
Joined
·
23,581 Posts
My cousin works at this plant and he said they were sending this to Evansville. I wonder..........................

 

·
Premium Member
Joined
·
6,616 Posts
Does that look like a stock head to you?
 

·
Registered
Joined
·
2,735 Posts
Yeah something is screwy with that.A black head.I wonder if it's a 350x head.Honda hasn't painted there motors black for a long time.
 

·
Registered
Joined
·
2,392 Posts
Discussion Starter #11
well thats wat we are doen to my moter
 

·
Registered
Joined
·
2,735 Posts
I just don't see it working.
 

·
Super Moderator
Joined
·
18,227 Posts
I could see it with 350X head but then you wont have a 300 engine now will you? no i don't think so... you plan on having this completed before the trip? If so you scared to run what you got now against my "X" ? to humor you I will still run your 395 set-up but when you miss third gear down the dragstrip dont ask for a rematch because the moose smoked you.lol All I'm saying is don't screw up because I know for a fact i wouldn't be able to beat you on a good run. Now If i got out and stroke out my engine and put in a 80mm piston 14:1 CPR and a flatside carb head work bigger cam. then you still won't beat the MOOSE. but instead i think im going to build up my other quad frame with a CBR700RR engine.
 

·
Registered
Joined
·
2,735 Posts
Now that'll beat him.
 

·
Registered
Joined
·
2,735 Posts
There you go mud.lol
 

·
Super Moderator
Joined
·
18,227 Posts
Let have a little math class.. shall we?..... ok
Specs of a stock 300EX are as follows....
Bore and stroke 74 X 65.5
Displacement 281.7
Compression Ratio 8.9:1

Now let's take Jons dream engine
Bore and stroke 85 X 69.5 (85mm piston / +4mm stroked crank)
Displacement (Uncalculated) 395
Compression Ratio 12:1

ok Now that we have all the specs in let's do some math.

bore X bore X stroke X .7854 = 394.3787
Now with that being said 395cc is possible IF you can show me an 85mm piston for a 300EX or even a 250X

let's realistically do this figure with an 80mm piston

= 349.34592
 

·
Super Moderator
Joined
·
18,227 Posts
This would require a piston with the Wrist pin to deck hight mighty close to the top of the piston and practically no skirt, I would really like to see this piston... Wiseco dosent make it I know I called. Just tell me where you will be buying this piston and crank you will also have to have a special Connecting rod too. and who is going to regrind your head to accomodate larger valves?
 

·
Registered
Joined
·
2,735 Posts
Moose I think he's insane.Just cause he saw something on ebay means it's real.LMAO!!!
 

·
Super Moderator
Joined
·
18,227 Posts
I have searched everywhere for a 300ex piston in the size of 85mm but I haven't come up with anything.
 
1 - 20 of 100 Posts
Top