Jetting for a hotcams

[GoLikeHell]

Hi Guys,
Well I installed a 11-1 compression standard bore piston and a hot cams 2 cam. Well I will say the cam did wake up the higher rpms, but now im having jetting probs. before I did all this i used to run a 165 main and the needle valve on the middle clip. Well it has a low end hesitation, and about 3/4 throttle flat spot. I dropped the needle one clip and the lowerend was a tad better but nothing to talk about. I tried going to a larger main 170 and it jsut chugged real bad. I jsut think its very odd having to jet down when changing to hp parts.

any ideas or yout thoughts are welcome. I would love to hear from others who have installed a cam and piston and how much jetting they had to do.

Thanks
Mark

[RED121572]

First of all, when you get your jetting right, post a report how that cam performs. My bike is TOTALLY apart as we speak and Im considering that very same cam.

The only two cts I can give you is to work with one circuit at a time. Meaning, tune one of the three jets one at a time.....that way, youll always know exactly where your at. Take "baby steps" when you rejet. Such as changing your main; use the next lower or higher main instead of going from a 165 to a 170. From my set up, Im using a 163 main. If I use a main that is just one higher, she bogs real bad. If I go one lower, she bogs real bad.

Hope that helped, if not, no harm done. Good luck man!

:D

[GoLikeHell]

Red I will give a complete update on the cam once its all tuned in. The reason I was asking the forum about Jetting is this is the first time I have ever added HP parts and had to put in smaller jets. I jetted my bike using a 5 gas analyzer when it was brand new and all i did was add a filter. I am going to use the 5 gas again for tuning once its out of the shop ( needed a new wideband 02). I will try and record and print out my data for everyone to see.


Thanks
Mark

[RED121572]

Uhhhhhhh.......a 5 gas what? Where can I get one of those?? lol

[GoLikeHell]

Red, 5 gas analyzer is used to determine how your engine is running. You can use this with a dyno and tune an engine perfect while under a load and crusing speeds. Mine is one of the first portable units, It's the same thing used for emission testing a car.


If you are interested in one you can find them on the OTC web site for alittle over 5K.

Enjoy
Mark

[440exnacsracer]

you shouldnt have to rejet with a cam. if you now have a "low" spot, this is normal. if you chose the stage two cam, you will lose a little low end and gain alot of top end performance. it shouldnt be anything to worry about though. if you are dissatisfied and want to put your stock cam back in, sell the stage 2 to me, im getting ready to buy one.

[Ketch]

Mr Golikehell I just did this a few months ago same piston an cam. This is the jets that are in mine at this time 165mj 40 pilot
needle last groove very bottum. I'm at sea level and the plug looks nice an brown. One thing the air box lid try it with out it.
I had 12 one inch uni filters in and it didn"t run just like yours. The unis are now gone.
I now have the holes covered now with Outerwares materal glud to the cover. The snorkel is coverd with a small Outerware cover to under the seat too. It was more of a problem getting it to breath than any thing. I plane on going to one size bigger jetts for winter
too. My air filter is a K/N with an outerware cover on it. I hope this helps. I also would like to hear want you find out with your test equipment.:cool:

[GoLikeHell]

Mr Ketch,
Thank you very much for writing in. I have been looking for someone who has the same setup and if they ran into any jetting problems. I am going to try and Jet mine like yours and see if that cures the problem, then once the 5 gas comes back ill have raw data to share with everyone.

How is your lowerend now? and did you notice alot of performance gain on top?

Thanks
Mark

[BadA$$440]

Originally posted by 440exnacsracer
you shouldnt have to rejet with a cam. if you now have a "low" spot, this is normal. if you chose the stage two cam, you will lose a little low end and gain alot of top end performance. it shouldnt be anything to worry about though. if you are dissatisfied and want to put your stock cam back in, sell the stage 2 to me, im getting ready to buy one.

Stage 2 is low-end and mid. Stage 1 is top end. Just so yo dont get confused.

[GoLikeHell]

Okay I just got off the phone with Hotcams, and here is the scoop. You shouldnt need to rejet if you just put in a cam, but since I added a 11-1 comp piston I will need to adjust it. Also since the 11-1 comp piston is more efficent it will need less fuel, so jetting down or changing the needle setting is required.

Thank you to everyone who responded to my questions.

One last thing, I asked what the difference was between the hotcam 1 and hot cam 2. Here is the results

Hotcam1, as discribed to me is a great replacement for a stock cam and you wanted more power. Does have more mid and some top.

Hotcam2, is a High RPM cam, and is made for racing. It will have less lowerend then a stage 1, but more mid and top end.

According to Tony at Hotcams, the best package is the 416 with a hotcams2 in it. So I guess Rico and the gang where holding out on us! LOL JK

Thanks
Mark:cool:

[Ketch]

Mr.Golihehell I didn't lost much low end at all you will slip the clutch
a little more but no big thing. i think that's the piston working to help the low end.
:cool:

[skemp]

My setup fricken' rips... It was such a huge improvement over stock. I have 10.8:1 comp, with the Hotcams Stage 2, bored to 415cc's. I need to get a header yet, and will have a port and polish within a month. I can beat my friend's R with a K&N filter and Boyeson rad valve, and my friend's LT with a Fatty pipe, bored .30, Boyeson reeds, and a few other things. Since racing those guys, I have switched out the rear sprocket for a 36 tooth. I can tell it has a lot more top end, but I can't ride it anymore because I blew the absolutely crap Cometic head gasket.