I bought my Raptor used from the dealer about a year ago. I found the original owner after I bought it and he gave me the story on the bike (he had problems with the bike, but that is another story,, and of course the dealer did not tell me about any problems). He said he spent a heap of money on porting the bike before he traded it in. I have finally got to checking it and sure enough, it is ported beautifully on the intake side!!! BONUS!!! Have not checked the exhaust yet. Makes me feel a little better about buying this thing, even with the problems I have had.

Anyway, how much of a power gain should I get from porting? I currently have E-series slip on, stock airbox (to be modded soon) and will be rejetting (still has original jetting). I believe it still has a stock piston. I have a dyno jet kit, but decided to try mikuni jets first. I am also thinking about getting a cam but do not want to invest in springs and valves yet (if I cam get away with that). I am going to match the instake boots to the ports today.

If I get a high compression piston, what other engine work will I have to do? Will I have to do anything to the valves?

Thanks

 

depends on the port job but i would say gains from 10-30 hp possibly

 

Raptordownunder- I hate to burst your bubble,but if it was ported the intake boots would have been done, To many items missing in this picture. [img]i/expressions/face-icon-small-frown.gif[/img] Maybe i am wrong, i hope so for you.

 

I matched the boots to the ports today, the head is definitely ported though. The boots were quite a bit smaller than the ports. I can see the grind marks in the intake and it is very smooth and finished in both ports. Took a while to match the boots but it turned out good.

I know it does not add up, I don't understand why someone would port the head and not finish the job by port matching the boots. Several things don't add up on this bike (I am finding out now, since the yam shop neglected to tell me). The guy that owned it said he had a high compression piston put in, valve work, high perf springs (he said titanium??,,,)and port work, (all that and no rejet!?!?) He said he took it for a first ride and it grenaded soon after (he said bent valves). He then took it back to the dealer and they re-did the job, again it blew on the second outing, this time throwing a rod and cracking the case. The bike was only a few months old and he demanded a new bike, which they reluctantly agreed to (the guy was raced and was sponsored by them).

They replaced the case (and I assume the rod and piston, but I do not know what piston).

This is when lil' ol' innocent/stupid me enters the picture. I see this near new Raptor at the dealer, shiny, clean, good price, only driven to church on Sunday, etc, etc, and I bite. They did a good job and cleaning up the engine work, I usually catch things that have been reworked, but at that point I wanted Raptor so bad I was blind. I did see where some bolts had been taken out and the plastic removed, but I was told they were "just checking things out to protect me, the innocent customer". I got it home rode for two days and then bolts started falling out everywhere. the rear axle nut came off and the rear wheel even came off. Needless to say i am not impressed with this dealer. I complained, but they basically said get stuffed. Live and learn,,,,,,

After I re-tightened every bolt, the raptor has been pretty good. I have it stripped down now getting new +2 a arms, rejet, steering stabilizer, +4 axle, body armour, new clutch, etc. I may even spring for a new cam and airfilter conversion from our local aftermarket guy.

Hopefully she turns out good, I just pray to the good lord above the second gear hangs in there.

Can tell me how to tell if I have aftermarket valve springs?

thanks

 

<< a good intake port jod should be rough and not smooth. >>



Defintely true. You need to keep the mixture atomized. Now the exhaust can be miror shined and as smooth as a babys butt.

 

From what I understand about porting, is, the bottom surface will remain rough to break up the gas (atomized) the sides up to the top will be smooth. The exaughst will be smooth.

 

Thanks for the info guys. By no means am I a porting expert, so when I said &quot;very smooth and finished&quot; it may have been misleading. When I said this, I meant no casting marks, lips or ledges, not smooth as glass. The ports are rough to touch, like it was finished with very rough sandpaper, with swirls and scratches. The bottom seems to be a little rougher than the sides and top, and I can see what appears to be a faint casting mark. I do not have a stock raptor head to compare it to, but I would imagine there would be some casting marks as on Car engine heads. I did some research about porting and from what I can find the recommended finish for intake ports is with 80 grit which is roughly the finish I have. (check out Porting)

I have not checked the exhaust yet, I will do that tomorrow.

I will try to post some pics, I would like all of your opinions. If anyone has pics of a stock intake port it would be helpful.

Thanks

 

Good luck. There are many smart people on this board to help you figure it all out. (not me)

 

Looks more and more like I'm screwed.

Airraptor, can you PM me an email address and I will send you a photo of the ports. I am having trouble posting the pics on imagestation for some reason.

14mins, agreed, I have learned more on here from you guys and I could ever dream of learning from the local shops.

Thanks a million.

 

Airraptor has confirmed it is ported, yee haa!!!!

Thanks airraptor.