Can anyone tell me the difference in the old style hot cams and the new style. I know the old style dosen't have the decompression mechanism. What dose that mean to my engine and my performance? Thanks

Both of the old style cams were exactly the same cams, just marked different. I believe they were also more agressive than the current set.

I would like all of the specs also! I have an old style intake, and Im looking to add an exhaust cam to it, or a new style intake, and move my current one to the exhaust...

Ok...so lets see...

Lift in mm ...(example = 9.1 mm)
Duration in degrees...(example = 238*)

Hotcam- Newstyle Stage 1- ...........9.1 @ 238*both Int and Exh
Hotcam- Newstyle Stage 2..............9.6 @243 Int and 9.1 @ 238* Exh
Hotcam- Oldstyle ............................9.6 @243* both Int and Exh
Yoshi-...............................................9.0 @ 236* Int and 9.3 @242* Exh.
Web Grind# 631/294-.....................8.7 @ 224* Int and 8.17 @ 218* Exh.
Web Grind# 293/536......................9.14 @ 226* Int and 9.6 @ 244* Exh.
Web Grind# 288/293......................9.35 @ 234* Int and 9.15 @ 226* Exh.
Web Grind# 288/540......................9.35 @ 234* Int and 9.75 @ 248* Exh.
Web Grind# 540/539......................9.75 @ 248* Int and 10.16 @ 256* Exh.
Megacycle X510..............................10.85 @ 257* Int and 9.78 @ 252* Exh.
DRZE Cams......................................8.92 @ 227* Int ans 9.3 @ 243* Exh.
Stock Z400/DRZ400S & SM cams-.............IN: 8.48 @ 227* and EX: 8.2 @ 243*

Duration refers to how long the cam allows the valve to be open in relation to one rotation of the crank. Simply put, a cam that has a duration of 243* allows the valve to be open for 243* of the crankshafts 360* rotation. In general, a very large degree of duration can help the high RPM stages, yet may hinder the low RPM's. Reason being the valve is/can be open at the wrong time during the pistons stroke.

The lift is simply how wide the valve is open. If the larger the lift, the more air that will enter/exit the cylinder. And as we all know, more air means the allowance for more fuel, which in turn creates more power.

Hope this clears up some questions about which cams will shine in what areas...

Here are the numbers on the Megacycle web site. I think it is important to mension that Megacycle's sound big in terms of duration, but they are measured at 0.040" of lift instead of the usual 0.050". Dont get me wrong, they are big, but they are not quite as big as they look by looking at the chart.

327 -x9 int. 0.385" lift 248* at 0.040" 104*lobe center Opens @ 20*btc Closes @ 48*abc

327 -x4 ex. 0.370" lift 252* at 0.040" 108* lobe center Opens @ 54*bbc Closes@ 18*atc

That is stage 1 Designed for stock pistons. Use R/D valve springs. Torque and strong mid range.
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327 -x5 int. 0.427" lift 257* at 0.040" 103.5* lobe center Opens @ 25*btc Closes at 52*abc

327-x10 ex. 0.385" lift 252* at 0.040" 108* lobe center Opens @ 54*bbc Closes @ 18*atc

Full race cam. Use R/D springs and high perf. piston. Strong accelleration, increased mid-range power + top-end.



Valve lash 0.008"- 0.010" intake 0.010"-0.012" exhaust

the old hotcams are the better grinds,more aggressive.

so, if i'm looking right, the stock EX cam is more aggressive than the stage 1 hotcam and Yoshi EX cam? so for a mild motor using a stage 1 intake cam with the stock ex cam would be ok? this question seems to come up once a week in here.

People have used the intake cam only with some success. Waaayyyy back when, during the first days of the release of the Hotcams, many members purchased the intake cam only (I was one of them). Keep in mind though, that was when the "Oldstyle", more aggressive cams were in production.

Is this for the before 05' models or after, b/c they say the 05' and newer have different cams? just wondering have an 05'.

I dont think the 05 and up cams are much different, if at all.

The DRZ bike engines used a slightly different cam profile than our Z's. I think they went to that profile in 05 and that's where the difference is.

Yep, that is what I am doing right now. I am about to add the ex cam to it though. I am pretty happy with my current setup though, it has power everywhere! But you can tell that its strong down low and fades after the mid.

Glad to see this pinned!

Thanks for the help! I think I'm gonna go with the webcams, I need to beat a raptor 660 and shut his mouth once and for all!!!

I have a DRZe ex cam in mine and it is somewhere between a stock cam and the Hotcams one - goes well and lets it rev alittle bit more free'r if thats any help ?

So how would you tell if you have the old style or new style? i have a great deal on some as new HotCams, both intake and exhaust, and am wondering whether they are new or old. is there a part number or something i could check??

Thanks
Dave

Well for one, the old style exhaust cam does not have the auto decompressor, and the new style exhaust cam does.

They do have different part numbers, but I dont know them. The specs are different also. The old ones were more aggressive.

Im excited! My old style cams are about to get broke in!!!

What is an auto decompressor?? LOL no clue what that is hehe..

Does anyone know the old style part numbers?? thanks
Dave

A mechanism on the EX cam that relieves cylinder compression on the compression stroke to allow the engine to rotate easier on startups. At least I think....

The auto decompressor bumps one of the exhaust valves open for an instant before TDC on the compresson stroke. Then once the engine is up to running speed, the decompressor is disengaged so it is like normal then.
It makes the engine easier to turn over, and it is ment to make it easier on the starter and related parts, or your leg. (depending on the engine)


Here are some pics of the difference




Both of the old style hot cams are the same cam, but they are marked different


These pics are not very old! That thing flat out rips now!

I still have the boxes from my oldstyle hotcams. it says 2003-1IN and 2003-1E

the NEW style hotcams are 2047-1IN and 2048-1E

hope that helps!

You need cams to outrun a 660 Raptor? What does he have done to that thing? When my bike was stock except for the Alba K&N kit I spanked a 660 Raptor with a full pipe, jet kit, K&N, and a lower front sproket. It would have to be a pretty well modified 660 to outrun a Z/KFX/DVX.

He has a big gun full exhaust, up'd the front sprocket to 15 tooth, magic box, and a cdi box. When i last raced him i had only a k&n power lid, dino jet kit, and 13 front and 42 rear sprockets. I just added a VCP Pulse Charger full exhaust and a Dyna non-programable cdi and the thing just rips now, BUT!!! Day two of testing the exhaust and jetting i somehow lifted the shifter slightly while flying in 4th and my trans got all bound up in there. Now she is stuck in 1st and the shifter won't move at all! Gonna bring her to a racing shop to get fixed ( i won't mess with the trany) and I'm gonna tell the dude to install any parts they make to make it bullet proof. While they are in there i want him to also install kibblewhite valves just for safty.

Swiped some more cam info from The Man (Burned at TT)... These are the cam stats for the DRZ bikes, along with Hotcams and RHC cams. All details are in inches, and the duration of lift is at 0.050":

S/SM IN .334 lift 227 dur EX .323 lift 243 dur


E IN .351 lift 227 dur EX .366 lift 243 dur


yosh IN .354 lift 236 dur EX .366 lift 242 dur


HC stage 1 (new) IN .358 lift 238 dur EX .358 lift 238 dur


HC stage 2 (was stage 1) IN .377 lift 243 dur EX .377 lift 243 dur


RHC 187 IN .356 lift 277 dur EX .356 lift 277 dur

Those stock DRZe cams are a significant inprovement of the stock DRZs/SM/LTZ cams...

hey could you help me out i bought a cam on ebay it was ment to be a hot cam but i dont no its the intake cam but it had no markings on it except dhr did you cams have any markings and what were they thanks man

The cam pics are a great illustration! I have to ask though, is that lithium grease you have on your cam lobes? If not, what is it? Next time I adjust my valves I'll be sure to take that extra step.

Thanks! (just registered...first post!)

Assembly lube.

is it possible to put a stage 2 exhaust with a new style stage 1 intake....

Is it possible to buy stage 2 hotcams still...if so where at and how much

no i already have it and was wondering if i can still use it w/ a stage one

You can put any combo together you want... Im currently running an old style Hot cams intake with a Web 540 grind exhaust cam. It works pretty good.

When adding cams is it necessary to rejet afterward?

The requirements will change a little, but most people will not notice the need for any jetting. However, if you are a little off already, it can exagerate it to the point where it will need some changes to run properly.

I would go ahead and change them expecting not to need any jetting, and see how it runs. The first thing I would expect to change would be the fuel screw because more aggressive cams really affect the intake pulse at lower rpms

what would be the best cam setup for an mx track?

Its not quite that simple... It depends on your other mods, and everyone has a different preference

My preference on a tight MX track or tight trails would be a cam setup for more low end torque. For dunes, drags, fast trails I'd want a cam profile made for mid-upper end HP. Just my preference...

Hey guys, I sent an email to Hotcams this morning asking them if there was any chance of remaking the more aggressive "oldstyle" Stage 2 cams and here was the response:

"Hello Adam,

We will not remake those cams. Our newer cams 2047-1 and 2048-1 make more power than those old cams in every part of the rpm range. Especially in the low end to midrange. The old cams only made more power in the very last 500-1000 rpms."

What do ya'll think?

I pmed you my thoughts...

To sum it up for everyone else (was a long azz pm) My opinion is that what they say is a sales pitch.

I believe the old style were in fact better over all, but could be weak off the bottom in a stock bore, stock compression engine. When adding the DRZe base gasket at the same time or a high compression piston, I believe it would be almost a total gain from idle to the limiter.

If you have stock bore, stock compression, and like to ride some gnarly trails, then the new style may be better for you.

If you ride MX, drag race, or run some wfo trails, I think you will like the old style better. Especially if you raise the compression!


If you run more displacement than stock combined with high compression, I would not even look at the new style hot cams because I can say that with the old style, I had absolutely no shortage of low to mid with them.


The old style cams were exactly the same, intake/exhaust, IMO this was for mass production and is also the only bad thing about them aside from weight. I have had very good luck combinding the old style intake cam with a bigger exhaust cam from Web.

I could go on and on, but I wont...

I think I'll just read about it again in OUR forum....

i have old style in/ex cams on both my z's, and my seatofthepantsometer says that guy is trying to up his new cam sales. i have 2 z's currently, one heavily modified, the other stock other than cams and exhaust. they both have insane torque down low, gnarly top end horsepower, and there isnt a flat spot in between. on top of all that, both of the quads have a perfect idle, and start great as long as the batts charged fully, (i wish i still had the auto decomp.)

I have a larger Web cam grind and I don't even notice the absence of the auto decompression unless the battery is low....but I fixed that by getting a 180 amp battery to replace the 120 amp stock battery. Auto decompression is only needed for the weak battery people and guys on 14:1 compression.

The old style cams have more lift, more duration, and better lobe centers - they outperform the newer versions in every way.

ANYBODY KNOW ANYTHING ABOUT TC RACING CAMS I THINK THEY HAVE 924 ON THEM I WOULD HAVE TO CHECK TO BE SURE I HAVE THESE AND NEW STYLE HOT CAMS DONT KNOW WHAT TO USE IN MY VENOM 434 14.1,TC PORTED HEAD BUILD ANY SUGGESTIONS

call tc racing. website is www.tcracingengines.com

ya i just got them back from tom a few weeks ago just wanted to see if anybody used them before

how did the old hotcams without the decompressor work for starting? was it more difficult in cold weather? I was on the hotcams website and only seen thier new style cams they didnt have stage 1 or 2 just 1 part number for intake and 1 number for exhaust.

They crank ok, but when used with high compression or a poorly tuned carb, after time it will take it's toll on the starter clutch. Im on my second one.

ya i have a 12.3:1 compression so that isn't really too high of compression compared to someguys run.

I have 2 years stock, 2 years at 13.5:1 with no compression release, some of which was with a carb that was causing it to kick back when hot. I just recently changed the starter clutch.

I would much rather have the bigger cams and change a starter clutch every once in a while than deal with the smaller cams.

There are ways around it also. I plan on adding a kill button next to my start button so you can get it cranking with no spark, then let go of the kill and bang! I think that will help.

When did they go to the new style? I picked mine up in 04 or early 05, back then they had stage one which was a intake cam and stage 2 which was the intake and exaust cam correct..
Also could you use the new style intake and put it in teh exhaust? if so what would you need to do? are the timing marks the same? thanks

how would an older style exhaust cam run as an intake and a new style intake used as an exhaust. Is the stock exhust cam just as good as the newer style hotcam?

I would always use a oldstyle cam for intake, and if you dont have another oldstyle cam for exhaust, use a newstyle exhaust cam because of compression relief (not that you need it on anything less than 13:1 compression)

no the stock exhaust cam is not as good, if it was noone would buy the newstyle exhausts lol. And if you got a stock bore you would be fine with stage 1 hotcams.