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Discussion Starter · #1 ·
well i figure its time for some more power so im looking at some build options and would like a little advice. right now im thinking 686 or 719/720 with...

high comp piston
new crank
hotcams stage 1 maybe more

i mostly ride trails and want it to be reliable but still make a lot of power. so i have a few questions with the reliability issues of going big on the bore size, hot cams stage 2 and up, and the higher high comp pistons.

i appreciate any help on this. would like to spend around $500 on parts
 

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Re: Ready to Build the Motor

If you're just looking for a strong trail setup I'd drop in the smallest 11:1 piston your cylinder will take and a cam; stage 1 if you're into power and stage 2 if you spend your time running flat out.

With that and the typical bolt ons (pipe/filter) you'll run right with most other bolt on bikes out there.
 

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Discussion Starter · #3 ·
Re: Ready to Build the Motor

ok, i think i want to run 720cc just cause and hotcams stage 1. now for compression, whats the highest i can go without having reliability issues? im thinking 12:1? i ride about id say 4 hours a week and dont really rag on it but i dont want to be pulling the motor back out in less than a year. now do i really need a new crank for this set up? id rather be safe than sorry but dont know if i need it for these mods. also i need to replace my one way and am scared at what i might see when i take it apart because i rode it about 2 months since it started going bad. so i think ill need a new 52 tooth gear also.

so does this sound like a good set-up so far?
720cc (what mm size piston is that?)
hotcams stage 1
12:1?

where can i find a good price on new "one way" and gear and is that all i need to fix that problem?
also, what is a good brand of piston to run?
and wheres the best price on the cam and is the "hotcams" brand a good choice?

maddog - thanks for the advice on that set up since that would suit my normal riding condition but i want to make sure i can whoop up on this guy i know with a 450r. and i think ill be going with the ct pipe and filter but run with my airbox lid since i follow some of my buddys on utes sometimes.

thanks for all help
 

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Re: Ready to Build the Motor

Some notes;

720 refers to the 719cc attained by a +4mm stroke and +2mm bore. There are "kits" to get this displacement but they require the purchase of a new crank and rod assembly along with the piston. If you want 720cc you can get it on bore alone, but it'll be 727cc and it requires machine work of the cases as well as a new sleeve.

If you go with a 720 kit I'd step up to at least the stage 2 cam otherwise you'll find the bike lacking on top end.

The largest you can bore on a stock cylinder is 102mm, or .080 over yielding 686cc total displacement. My guess is this is more in line with what you're thinking about. If you build mildly you shouldn't need to replace your oem rod or crankshaft.

The more compression you get the higher octane you need to run and the more stress on the motor. 12:1 will require race fuel either straight or mixed with pump fuel in order to run properly unless you are at a high elevation. The reason I suggested 11:1 is because that is the highest compression that can consistently be run on premium pump fuel from your local gas station instead of paying the higher price and having the limited availibility of race fuel as a necessity.

You're looking for an L&A Designs one-way, you can find them at Ripper Racing, Alba Action, RSP, eBay, and other online retailers. Prices are pretty constant, 250 or so for the kit w/ one-way and gear. That will fix most of the starting problems associated with the raptor, most notably the "freewheeling" noise and spotty start up.

Wiseco, Ross, and CP make excellent pistons. I would not run a 100-102mm JE, or at least a standard one, because of their poor track record. If you do prefer JE, I'd suggest getting a beefed up one from Sparks or another builder.

Hotcams is a good choice, best price is going to be online at a retailer or eBay.

The CT pipe is a good choice, I ran one for a couple years and was very happy with it.
 

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Discussion Starter · #5 ·
Re: Ready to Build the Motor

thanks alot maddog, it seems whenever someone has a question you are always the first to respond with helpful information. knowing that now, it seems 686 is going to be better for me and 11:1 is better since i can get premium anywhere and i know a couple places in town with the race gas and its expensive. i think the stage one cam will be good for this setup since its mild and i dont need stiffer springs.

so when i go to the machine shop i tell them to bore it .080 over right? and i order a 102mm piston and all will be good

ive herd about the JE pistons cracking and stuff so ill just stay away from them and choose probably based on price between Wiesco, Ross, and CP.

was the CT pipe too loud? i dont want it real loud but ive herd they make the most power so thats what attracted me to them. are their any other pipes that make that much power and are not real loud i should look into?

ill order the L&A soon, it sounds good.

now....can you give me maybe a rough estimate of how much hp i should be making with this set-up? i dont want to have to worry about the 450's. and the 660's make like 38hp stock right?

thanks again :thumbsup:
 

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Re: Ready to Build the Motor

You'll actually want to take the new piston along with the jug into the shop. The bore needs to be done according to the piston's specs, not the listed size.

Wiseco is going to be cheapest by far, 125-150 compared to 180-275 for Ross/CP.

The CT was certainly louder than stock, but not any louder than many other pipes on the market. The bonus with the CT is that by removing a disc or more you can cut down sound without too much drop in power. I was very happy with the performance of the pipe and if I was running a single I'd still be using it.

Stock hp is around 35. Pipe, filter kit w/o airbox lid, 11:1 102mm, stg1 cam on stock carbs and head should put you somewhere in the range of 50-53hp.
 

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Discussion Starter · #7 ·
Re: Ready to Build the Motor

well i think im all set, just have to wait till the 31st when i get my paycheck. not sure if im going to install the cam and piston myself yet. i have a lot of experience working on car engines (replacing head gaskets, rod and main bearings, etc) but no experience on atvs or motorcycles so im going to talk to a couple shops i know tommorow and get an idea on labor. but the parts are going to be cheaper than i initially thought so thats good.

i think ill be very happy with the performance and cost. thanks for all the help, ill post my progress
 

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Re: Ready to Build the Motor

Maddog definately covered your options well. The only advise I have to give is that built motor's really prefer the dual exhaust systems. Since you're planning on buying a new pipe anyway, LTE's and Barker's have been dyno proven to make 2-4 RWHP over any single exhaust system on the market.
 

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Discussion Starter · #9 ·
Re: Ready to Build the Motor

i didnt know they made better power, seen a lot of people running them though and was curious. does it sound good with dual pipes? if they make more power then i may go with duals but i have never herd them
 

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Re: Ready to Build the Motor

John said:
i didnt know they made better power, seen a lot of people running them though and was curious. does it sound good with dual pipes? if they make more power then i may go with duals but i have never herd them
Duals really don't sound any different than singles.
 

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Discussion Starter · #11 ·
Re: Ready to Build the Motor

i just thought for some reason it would sound different with 2 mufflers, if they sound good and make good power then i guess ill go with them. they sure are expensive though.....like $700 for LTE or Barkers. between LTE and Barkers, which is better - sound and performance wise? because they both cost about the same.

ive seen a couple used systems on ebay for around $400, would that be a good route? i dont really care if its a little scuffed up but if mufflers wear out then maybe i should just go new. one guy claimed he only had it on for 4 rides
 

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Re: Ready to Build the Motor

I'd go with the LTEs, the out of frame barkers can be a hassle for trail riding. If you can find a used set with only cosmetic blemishes and not dents and creases they'd work fine.

Duals work very well, but as was said they are considerably more expensive than most singles.
 

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Re: Ready to Build the Motor

John said:
i just thought for some reason it would sound different with 2 mufflers, if they sound good and make good power then i guess ill go with them. they sure are expensive though.....like $700 for LTE or Barkers. between LTE and Barkers, which is better - sound and performance wise? because they both cost about the same.

ive seen a couple used systems on ebay for around $400, would that be a good route? i dont really care if its a little scuffed up but if mufflers wear out then maybe i should just go new. one guy claimed he only had it on for 4 rides
I wouldn't be afraid to buy a set of LTE's used. The pipes are stainless and the muffler's are aluminum. So they should hold up well. The muffler's are also repackable.
 

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Discussion Starter · #14 ·
Re: Ready to Build the Motor

Alright so LTE's it is. I will keep shopping around for a nice used set while i do the motor work. Probably going to start tearing the bike down today.
 

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Re: Ready to Build the Motor

John said:
Alright so LTE's it is. I will keep shopping around for a nice used set while i do the motor work. Probably going to start tearing the bike down today.
Fun stuff. :thumbsup: I tore the head off mine Saturday so my engine builder(Kenz) can port match the new intake manifold to it.
 

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Discussion Starter · #16 ·
Re: Ready to Build the Motor

Well today is payday so its time to order the parts. I got the bike all ready to install them and found good prices on the Wiesco and Hotcam but have a question on the one way. I found one on ebay for only $120 but it says its oem and straight from Yamaha. Will it be improved from yamaha and a better design then the one i have now? I dont think its better because you guys said to just get the L&A, but i want to make sure before i buy the L&A.

http://cgi.ebay.com/ebaymotors/ws/e...STRK:MEWA:IT&viewitem=&item=4633523264&rd=1,1

then this is the L&A for $195 (ill order the 52 tooth gear seperatly if it looks like i need it)

http://cgi.ebay.com/ebaymotors/ws/e...RK:MEWA:IT&viewitem=&item=180047227704&rd=1,1

ALSO......any suggestions on air filter setup? i dont want to have to worry about mud and water getting in there so i was thinking of the Outerwears Lid and then some kind of high flow filter but im not sure on brand.

i think that about covers everything, still looking around for best deal on the LTE exhaust Thanks again for the help
 

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Re: Ready to Build the Motor

DO NOT GET THE OEM ONEWAY!!! They all suck, the changes made from 01-02 and 03-04 didn't help the matter. Go L&A and get the gear too, if you don't need it you can always return it.

If you're going to keep the stock airbox you'll want a pro-design billet adaptor kit with either a foam or K&N filter and an outerwear/precharger. Personally I'd skip the 100 dollar airbox lid unless you're into water crossings and deep mudholes; and in that case I'd keep the oem lid and just modify it to breathe better.
 

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Discussion Starter · #18 ·
Re: Ready to Build the Motor

ok, i will get the L&A for sure with the new gear. but this is what i was thinking with the outerwears -

http://cgi.ebay.com/Outerwears-airb...ryZ88433QQrdZ1QQssPageNameZWD1VQQcmdZViewItem

i dont go through deep water but sometimes ill splash through real fast and im always happy it doesnt get water in it. my old blaster was not sealed nearly as good and if i hit the same water i know in the blaster it would have got water in the engine
 

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Re: Ready to Build the Motor

Just a word of advice, the duals are better than the single performance wise, but like maddog said... You can take disc's out of a CT (easily)to quite it down (with little loss of power) when you need to (like at state parks, most communities, ect). If you do all of your riding out in the middle of the dunes, middle of nowhere, or use it just to drag race..the duals are not a problem. For future reference.. if you ever decide to get fcr carbs, they won't with the ct pipe, or the lte's,...unless you invest in the aftermarket kits that can make them fit..Well thats my understanding of that situation...I believe maddog knows more about that particular problem.
 

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Re: Ready to Build the Motor

The LTEs have quiet cores that work well, but I don't believe they're included and they aren't lossless.

CT will work with FCRs if you order the special midpipe, but it will cost you a little power. If you plan on FCRs in the future, skip the CT and go straight to the LTEs. (I think he said he was going with the LTEs anyway). They fit with FCRs but take a little coaxing. I was actually going to run my ct with the special midpipe but I found a friend who wanted it and I talked myself into a set of barkers.
 
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