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Discussion Starter #1
ok So Ive decided to rebuild my engine that was blown due to lack of oil... Right now I have two main questions... also I want to know of some aftermarket parts that should be bought while I have it torn apart or which parts are better stock.. for ex my mechanic told me that a stock crank is better than a hotrods crank and Im new into the realm of ATV engines so anyhelp would be appreciated...
Keep in mind that 1. I dont want the biggest and baddest part just good value for the money.. not expensive but not somethings that just gonna break with 20hrs on the engine either...2..The only real power enhancers I was looking at before the engine blew was a 11:1 Compression Piston and a Hotcams Stage 2 Cam.. thats really all I want as far as power goes to give you an idea..so here are my two questions a.t.m.

1. What would be the better crankshaft to put in this thing for the money & Im talking longer term reliability.. Stock?

2. I need to buy a new clutch and basket since it was run out of oil.. what would be the better clutch to buy? stock or aftermarket

I know that most aftermarket parts are better than stock parts but my mechanic told me with the crank especially if you buy an aftermarket and it breaks the rod then the whole engine is completely destroyed and I dont want that... so any of you people that have had the expierence with all these parts and shopping please give me some insight.. so far Im looking into around $2000 at max for the total build not counting labor because I have to buy a new one of everything pretty much lol..
-Thanks in advance
 

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If it's too loud your too old
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Well even a stock crank if it breaks a rod will destroy the engine. It kinda sounds to me that the first thing you need to do is find another mechanic because he is misinformed! IMO from what your describing a nice 734cc build would be just fine for you, stock stroke Hotrods crank 105.5 CP cylinder and 11:1 piston HC3 cam and a mild +1 valve port job with a +3mm throttle body. Tuned right you'll have a solid 65hp range very reliable Raptor.
 

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Out of curiosity, why for the same money not go with the +5 crank since your there anyway?
 

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Discussion Starter #4
Well even a stock crank if it breaks a rod will destroy the engine. It kinda sounds to me that the first thing you need to do is find another mechanic because he is misinformed! IMO from what your describing a nice 734cc build would be just fine for you, stock stroke Hotrods crank 105.5 CP cylinder and 11:1 piston HC3 cam and a mild +1 valve port job with a +3mm throttle body. Tuned right you'll have a solid 65hp range very reliable Raptor.
Sounds confusing and expensive lmao.. Im new and retarded here lol I speak guitars so I apologize for my ignorance
 

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Discussion Starter #5
Out of curiosity, why for the same money not go with the +5 crank since your there anyway?
I didnt want to go the stroker route cause I do plan on keeping the Raptor for awhile.. hopefully atleast another 2years with no hassle out of the engine.. Trust I already looked at that 778cc I think Big bore kit that comes with the cylinder,piston, and crank.. its still runnin through my mind haha but I want my reliability.. thats why I chose a Raptor over a YFZ450
 

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If it's too loud your too old
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Sounds confusing and expensive lmao.. Im new and retarded here lol I speak guitars so I apologize for my ignorance
No problem, The cylinder, piston, cam, valves and crank you have to buy anyway so that stuff is not going to be any more expensive than stock stuff. the only real extra expense will be the port work and the throttle body so in all reality it won't be a whole lot more than building it back stock.
 

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Discussion Starter #7
No problem, The cylinder, piston, cam, valves and crank you have to buy anyway so that stuff is not going to be any more expensive than stock stuff. the only real extra expense will be the port work and the throttle body so in all reality it won't be a whole lot more than building it back stock.
Idk of anyone around here that can do that kind of work and Ive looked one TQS's site and together it would be like a $300job i think not counting shipping.. and also I still need to buy a PCIII,Intake, & Exhaust with me puttin the high comp piston and cam in there...

I was getting ready to buy the big 3 right before it blew up.. maybe its a sign?
On the bad note I just a bought my new set of Razr2's 1week before It blew up lmao...
 

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i saw in your other post that you said your complete head is shot. what do you mean by that? the head itself, or just everything in it? if you check the for sale section you could probably find a stock or already ported head for cheaper than buying everything new.

i'm with flwoods on his suggestion. but if you don't have the cash for a big 3 after the rebuild, it will still run. just get a controller, and pull your sparky. i know its not the ideal setup, but it will run. which at this point is a 100% improvement right? then when the money comes in, you will get alot more power than anyone else has gained from getting an exhaust and intake.

+1 on the mechanic though. he doesn't seem to informed on things. aftermarket is almost always better than stock and is also cheaper or the same price. no brainer imo.
 

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Discussion Starter #9 (Edited)
i saw in your other post that you said your complete head is shot. what do you mean by that? the head itself, or just everything in it? if you check the for sale section you could probably find a stock or already ported head for cheaper than buying everything new.

i'm with flwoods on his suggestion. but if you don't have the cash for a big 3 after the rebuild, it will still run. just get a controller, and pull your sparky. i know its not the ideal setup, but it will run. which at this point is a 100% improvement right? then when the money comes in, you will get alot more power than anyone else has gained from getting an exhaust and intake.

+1 on the mechanic though. he doesn't seem to informed on things. aftermarket is almost always better than stock and is also cheaper or the same price. no brainer imo.
yes anything is 100% better right now.. but I planned on putting in the duals,air intake and FI controller after the build regardless because I hate running that stock pipe.. it has no balls at all lol..

about the mechanic I might have mis typed that.. What he told me was that he had put hotrod cranks in peoples engines and they where comin back broken.. so i guess that product is like a 50/50 crapshoot for some people... he then told me if you break your crank and it throws a rod then its pretty much a S.O.L. situation and I can believe that because a Hotrod crank is like $185.. thats way too damn cheap haha

Also he wasnt refering to buying stock parts on most of it.. just buying the parts to Stock specs.. so I guess I should have cleared that up a bit.. sorry about all of this.. Ive got 190,00,000 things running through my mind a.t.m.
 

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i have heard of some hr cranks going bad. there are other companies out there that are more reliable. i'm thinking falcon crank? don't waste time searching that unless someone says thats what they are. :lol:and going with stock bore or stroke isn't a bad thing. but neither is big bore and stroke if its done right.

my only advice to you is stay away from trinity. i have read many bad reviews on there bb cylinder. good luck with the build and keep us posted.
 

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Hot rod cranks are $285. That being said the stock crank seems to go bad for no reason sometimes. Happened to me and there was nothing showing why. Do a search and you will find more bad stock cranks than HR cranks that they are replaced with. At one time High Dessert Dyno had stock used cranks for $120. The other options for a crank are Barker and Falicon. Both are great but will cost you half the budget you have. My vote is for the 778 stroker w/ a HR +5 crank. You will end up there anyways and it will cost the same for those parts. Buy a book or download it and do it yourself to save from some headaches and money.
 

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Discussion Starter #12
ok guys heres an update

Figured out my head is ok and I can use it...
So far this is what Im going with

Hotrod crank stock stroke
JE 11:1 Piston
Hotcam Stage 2
Kibble White Valves
PC III controller
DMC Force 4 Dual Exhaust (in the future)
Pro Design Foam Intake (in the future)

My main question a.t.m. is my cylinder is still scarred badly
which is the better bang for the buck deal... and remember I want reliabilty over power

heres my three options pretty much
1. Buy a replacement stock cylinder which is like 500bucks

2.Have it bored it a 103mm which makes it a 700cc on a stock stroke

3.Bore it to a 105.5mm which makes it a 734cc

Heres my problems/questions with the options i have
1. Its more expensive and I know it will last the longest
2. Im not sure if boring to 103mm is enough to get the scarring out of the cylinder
3. I think 105.5mm is a little too much for what I do.. Im a trail rider.. occasionally i get on the MX track and mess around but Im an aggressive trail rider first and foremost
Im sure by going to a 105.5 means it will run hotter as well and do more wear and teat on the engine which is what I really dont want.. How bout some of you guys that have these things bored? how is your reliability on em? without tearing into the engine to spruce em up
 

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From The Stix 2 Da Brix
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I ran a low compression 734 for about a year. It was great in the woods. I'm now stepping it up to a high compression 778 cause I want 80hp or better. It's still gonna be my trail bike,just a handful to ride in woods. I love challenges so that's why I'm getting the handful.
 

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Discussion Starter #14
I ran a low compression 734 for about a year. It was great in the woods. I'm now stepping it up to a high compression 778 cause I want 80hp or better. It's still gonna be my trail bike,just a handful to ride in woods. I love challenges so that's why I'm getting the handful.
whats low comp? the stock 9.2:1 or the 11:1
I know with both u can run pump gas which is what I want.. I really dont want to mix for the hassle and for the price lmao
 

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From The Stix 2 Da Brix
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11:1 with a +2 head and 5050 cam. Now I'm going 13.5:1 778 and 54mm TB. Really reliability comes down to how ya maintain your bike.
 

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If it's too loud your too old
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If your gona buy a cylinder (which is the best way to go) you might as well buy the 105.5 cylinder with the 11:1 piston it will be just as reliable as a stock bore.
 

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From The Stix 2 Da Brix
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If your gona buy a cylinder (which is the best way to go) you might as well buy the 105.5 cylinder with the 11:1 piston it will be just as reliable as a stock bore.
+1 never had a problem myself.
 

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Reliability is in relation to power. Not compression, stroke length, or bore diameter. Its the power that puts strain on the motor and its individual moving parts, not what one moving part does. Sure getting a 105.5 cyl is probably a safer bet than getting a stock cyl bored and nikasiled; but to what extent? I've ran my 734 bore/nikasil for 2+ yrs.
 

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Discussion Starter #19
If your gona buy a cylinder (which is the best way to go) you might as well buy the 105.5 cylinder with the 11:1 piston it will be just as reliable as a stock bore.
If I went went with the 105.5 cylinder with the 11:1 piston and hotcam.. Would I be alright with the rest of the engine being stock?

for ex Would i need bigger fuel injectors or a bored throttle body? or can I run that stuff stock and it wouldnt hurt the engine?
 

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If it's too loud your too old
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If I went went with the 105.5 cylinder with the 11:1 piston and hotcam.. Would I be alright with the rest of the engine being stock?

for ex Would i need bigger fuel injectors or a bored throttle body? or can I run that stuff stock and it wouldnt hurt the engine?
No you'd be fine, but anything else you add from there would just be a improvement.
 
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