Engine choice - why?

[Logan #34's Dad]

Just curious as to why I see most of the Mods with either a CR85 or a RM85 power plant? When I talk to the dirtbike people, they tell me that NO-ONE is winning on a Honda. They tell me that the KTM and Yamaha are the strongest engines on the track. They do same the Suzuki is strong as well.
So, tell me why these Honda's are so popular? If I had to guess, we see kids winning with the Honda engine so we follow suit......

[riding4fun]

For me it was parts availability. Easy to come by. No other reason.

[rookiewrench]

If you look at the Loretta Lynn results from last year the Suzuki, Yamaha and Kawasaki seem to dominate the top 10 with no honda or ktm in the mix until later. In the super mini class the honda seem to step it up and have a championship and a few top 5 postitions. These results were from last year.

Rocky, I am sure that you will purchase what is ever most economical for you. lol. As you know the 2 fastest kids this year have a suzuki, Cam Covil, and a honda, Brett Musick. If you plan on a super mini get the 150r motor.

[gistmarrs]

I think part of it is that torque is a bit more important than Hp in a quad vs. a motorcycle. Also, the rider makes a huge difference. Some riders will be faster on the Yamaha than the other motors, other riders will be slower.

The Yamaha's do not have power valves and suck at low RPM torque, but scream at the higher RPM.

The Honda is getting old as they haven't made a two-stroke in a few years.

The KTM's parts are probably twice as expensive as the others.

I have switched out the Yamaha's for Suzuki's, but I would love to try a Kawi or KTM. If you want to try a Yamaha, I have two that need new homes.

Thats my take on it.

[edwardsp&b]

I'm not sure which would be the best, but I will say that between our two mods I like the powervalve motor better. It just has more grunt on the bottom compared to a non powervalve. I also have been very happy with the rm. Rocky, my opinion to u would be to go with a motor that has a powervalve, you'll be happier in the end.
Bryan

[Logan #34's Dad]

Hey Bryan, it sure would be cool to keep it all Yamaha. I'm thinking KTM....

[T@AFP]

Based on the RM,is there a specific year that is preferred? What pipe seems to be best for it?

[edwardsp&b]

Im not sure on availability, but our Rm is really strong with the Trackside pipe. I was told that there were not anymore yet, but I didnt confirm it. I will say that it is screaming fast with that pipe on.

I dont ride his quads because im so big, but I rebuilt the rm 85 the other day and wanted to break it in myself. WOW!! I cant believe how fast it is.
Bryan

[Logan #34's Dad]

All I know is I watched Brett Musick pull ALMOST every holeshot in the 90 Mod and Supermini with his Baldwin tuned CR85 and CR105.... With that being said, when Alec Miller got it right he was wheel to wheel with Brett on his Tommy Alley tuned RM85.... Decisions.....Decisions....
But, if you ask around the dirt bike community, the CR is not even a top runner. I've spoke to a friend who's track hosts a Loretta Lynn's qualifier, he says the Yamaha is king and the RM and KTM are a very close 2nd. He cannot believe we use the CR"s.
I told him that someone ran one and won a couple races and everyone had to have that motor..... Typical mini dad's. :devil:

[chunky0071]

I am going with the rm but thats just because I picked up the whole bike for 150$ with bad rings. Was looking for a KX 85>

[T@AFP]

I really favor the ktm only based on the mods we've built lately. But Im not to sure on reliability and repair/maintenance bills. I have a opportunity to buy a fast proven cr but.....
I want to make a decision soon on our mod for next season.
Kinda leaning toward the ktm though.

[zach R 7x]

Hey Rocky, we just got our pister running w/ the cr 85 w/ fmf gold series fatty pipe in it and this thing is just plain sick!!!! We bought it used with all the stock componets, very little tunning and always starts on first or second kick! Fast as hell!!!

Can't go wrong with Honda!

[Logan #34's Dad]

Tim, you sure are going to be upset when a 2fast cvt smokes your cr to turn one...:devil:

[jake55]

we run both quads and bikes and i have no problem saying out of the box the KTM is superior to all other brands as far as bikes go. the initial cost is greater but it is ready to go when you pick it up. all of the other brands will need some $$ before you can be ultra competitive. keep in mind, in the dirt bike side most kids wont use all the power in any of them, so the extra money is kind of a waste. some of you have talked about the power valves, yes it makes a huge difference, i believe the KTM started using it on the 09's and newer. i have not tried the KTM in a quad but have asked alot of questions since i have a ktm motor already. for the most part i have got the same response from everyone. ktm = expensive, lack of parts available and here's the big one that scares me, the crank tends to be the weak spot when in a quad due to the extra 125+ pounds.

[T@AFP]

[ ktm = expensive, lack of parts available and here's the big one that scares me, the crank tends to be the weak spot when in a quad due to the extra 125+ pounds. [/B][/QUOTE]

Hmmm scares me too.

Our crank went at Lorettas in our KX65 mod too.

I hear the cranks are expensive too on the KTM's.

[edwardsp&b]

When you say Cr 85 in the dirtbike world they all laugh....... All you ever hear is yz 85, and ktm.

I think the powervalve helps the low end power on a quad more than not.

On another note, I have a really fast ktm 65 dirtbike for sale that placed 2nd 2 years ago at Lorretta's. I didnt use it because I wanted a powervalve motor. If you want to try Ktm I will sell it cheap, just been rebuilt with probably a couple of hours on it. Ill take 1100.00 for the bike.

BTW the whole rebuild, top and bottom incl. crank, was like 6 or 7 hundred and some change. The crank is what cost the most.
Bryan

[Logan #34's Dad]

KTM cranks are expensive:::: I laugh at that. When you pay $650 for a damn 2fast crank..... I bet the KTM crank don't cost that!

[gistmarrs]

That is true.

We complain about the cost of a rebuild on a KTM being a couple hundred dollars compared to about a hundred on one of the Japanese motors and the CVT guys are paying way-way more to rebuild there rt's and 2fast.

I do love our hybrid quads. There fast and relatively cheap compared to some of the other options out there.

[zach R 7x]

Originally posted by Logan #34's Dad
Tim, you sure are going to be upset when a 2fast cvt smokes your cr to turn one...:devil:

I am sure this will happen Rocky and my demeaner now is who cares? In it for the fun of it now, totally lost the drive to keep up with the jones in this stuff anymore. What we have is what we have.
Oh bythe way I will be the one that is relaxing next to my cr85 watchin the guy with the 2fast scamblin to tune before the next race! LOL!!

[T@AFP]

I did some looking around yesterday and found most of the parts to be close to the same price for the ktm and the cr and RM. Except the crank. It's 80.00 more.
On that note, I ordered the ktm 85 engine. Looking forward to getting it in and doing away with the lil kx65.

So if any one needs a kx65 engine....lemme know.

[jweidner]

honda uses a different "rod ratio" than most other manufactures, by doing this you will produce more torgue. Suzuki's ratio is actully pretty close to the honda. Anything above a 1.75 in my opinion would not work well.

[T@AFP]

Originally posted by jweidner
honda uses a different "rod ratio" than most other manufactures, by doing this you will produce more torgue. Suzuki's ratio is actully pretty close to the honda. Anything above a 1.75 in my opinion would not work well.



?????
What does that mean? Are you referring to the KTM on rod ratio?

[jweidner]

I was refering to CR vs KX, YZ and RM engines. I have not looked into the KTM, however I have a pic of a KTM 85CC production quad that looks to be pretty nasty from all the reviews I,ve heard.

The higher up in rod ratio you go the higher your usable power goes. If you have 1.90 rod ratio your power band will come in at a much higher rpm causing little torgue on the bottom end. If you have a ratio that is around 1.65 now we have a 2 stroke with some torgue and will still have top end.

Rod ratio is determine by rod length, does increase cc's just changes your torque curve.

CR 250 are the 2 stroke of choice being they have incredable usable power range.

Thanks,

[jweidner]

sorry, meant to say rod ratio DOES NOT increase cc's

thanks,

[quad59]

Living in the bike world these days the ktm in my opinion would be the best the newer models make the most all around power utilizing the power valve and they are already set for a hydraulic clutch. Ktm parts are going to cost more than the Jap models and your availibility is also limited. In the quad world how many people are actually running ktms so if you didnt bring spares your not going to find any to borrow. Suzuki and Kawasaki are pretty much the same from the bike sharing days back in what was it 02-05 no major changes and are known for a more linear powerband. Yamahas build power high in the rpms where most bike riders pin it on a machine weighing a half of what your quad will. Honda is a dime a dozen,makes good power and you will never have trouble finding parts for them. Ktm if money is no object stick to red for the budget minded simplicity of the whole thing just my .02 cents, but those KTM motors are sweeeet :)

[jweidner]

Agree!:)

[FISH ON!]

Originally posted by jweidner
I was refering to CR vs KX, YZ and RM engines. I have not looked into the KTM, however I have a pic of a KTM 85CC production quad that looks to be pretty nasty from all the reviews I,ve heard.


The quad in your PIC is in the latest Dirt Wheels magazine and is made by E-ATV Racing in Europe and is a dirtbike conversion, not KTM production. Article says it is a real winner.

[stevo7706]

that ktm is what i want!

[jweidner]

sorry about that, looks like a may not be able to read too well, has a KTM engine and looks like a KTM, didn't see it in dirt wheels though..

[jweidner]

Never the less.... it looks like a bad motor scooter....

[T@AFP]

I'm going to have to look into that little quad. Looks very cool and it's orange!!
Well I spoke with a couple dirt bike engine builders today and asked about the rod ratio. Most agreed that by putting these motors into a mini quad. The RM would be best suited due to the power valve. However, the ktm seems to be a better runner in bikes Also, with a slight engine mod the ktm maybe a better choice.( May be)
I'm all about trying something new. Usually bites me in the ars but whatever.
So I ordered a 08 ktm 85 today and I'll do the engine mod.
As far as borrowing parts at a track. Like most guys I try to have spare parts or engine. Chit I just retired from the cvt world. I had spare everything.

[jweidner]

Be honest, unless your going in a circle and can really distinguish motor vs driver I don't think you'll be able to tell the difference. I think the KTM,s always seem to be better when talking about torque. They have a totally different kind of power when comparing it to the YZ that does not have a power valve.

I don't think you'll be disapointed in the KTM... and no matter what happens...still won't break parts like a cvt.

[T@AFP]

I don't think you'll be disapointed in the KTM... and no matter what happens...still won't break parts like a cvt. [/B][/QUOTE]

Amen!!
Thanks for all your help and w raptor 125 questions I had

[stevo7706]

so what is the opinon of a crf150 vs a 2stroke? what advantages would one have over the other? we're looking to move out of the cvt's.thanks to all!

[jweidner]

That's a tough one.... talking to dirt bike guys, they tell me the 150 can't compete with 2 strokes. I,m not saying they couldn't, I don't think alot of time was spent with the 150. Where I live there is only 2 150's out of a class of 15.

I think when the 150 was build, honda was hoping that the other manufactures would follow and they just never did.

Just my opinion...

[quad59]

take into consideration that most of the crf150's in the bike world race in a supermini style class allowing for a 105cc 2 stroke. I dont think they compete well against a mild built 85 or a supermini machine but thats in the bike world. On a quad though the torque is going to be better and may be what your after but the people i talked to said they are bigger grenades than the 250f's and cost just as much to fix. If I was going to build one for a quad I would def. have it built to make optimum power in lower rpms, save you some reliability, your also going to slightly heavier with a fourstroke than a two as well.

[jweidner]

couldn't agree more quad59

[rookiewrench]

I guess if I was going to buy based on what the bike guys do I would buy a Suzuki or Kawasaki ( if you can get it to work). If you look at the results from lorettas Suzuki and Kawasaki dominated. KTM didn't even podium until the supermini class with a third. I understand that suzuki and Kawasaki may offer better sponsership deals then the others but if you can't win on ones bike they wont ride it .

If price is the issue, the ones coming from CVT or Cobra won't mind that expense for KTM. If you base it on stock power I wonder how many are going to keep them stock. Most will stroke them to a 90cc anyway and where are you then.

My son has had a 90 mod with a suzuki motor and a super mini with the honda and likes both of them but prefers the suzuki 2 stroke but the 150r is much more forgiving. I would suggest on with the power valve for the low end power.

Just one persons opinion

[Hetrick Racing]

One thing to say; if you decide to go with anything but a Honda (which they all are good) make sure you have your own parts for spares, motor,electrical,the parts for the mods are not common to fail but,hate to drive to Minn.and loose a stator.That would be a long drive home, I only carry Honda with us Baldwin Im sure is the same, I think JB is the same, Tracy may have some zuk stuff.But really your kinda on your own.

[Logan #34's Dad]

If there is one thing I've learned with mini quad racing is that whatever a kid is riding that wins - everyone will follow. So, if an incredible rider wins riding a JB with a CR85 then WE dad's believe our kids will be able to win with the same thing.
I've always said, If I were to hang a bag of crap off of Logan's grab bar and he wins, the next race everyone else will have a bag of crap hanging off their grabbar.
With all that being said, a CR is the "flavor of the month" but as soon as someone with an RM or KTM wins or holeshots a couple races - that will be the new "gotta have it".
Example, DJ Bassani puts it on everyones arss at Loretta's with an actual Cobra motor - Good-bye KX65s.........
Sepesi kid smokes the field on his Cobra/CR 90 engine........ all the other dad's will be buying that combo.....
So, to the dealers and parts suppliers, you can stick with what you have - and be the same ole same ole or think outside the box a little and be ready to corner another upcoming market..
You put Brett Musick or Cam Covil on a KTM engined quad - they'd still won the races. Talent!!! Then we'd all be buying up the KTM's.

[Hetrick Racing]

Just remember the 90 mod started out of the Honda shop,
Bud made the first one


By the way as the old saying goes

You meet the nicest people on a Honda lol

As I said, I think all of the new product is good, I mean it is 2011,I wouldnt waste much time picking an engine,,, get the kid on it