Opinions on TRX 310 power?

[dawnchris]

I'm REALLY debating on whether or not to try a 310 kit on my 250R. I've heard good and bad. Mainly, I've heard they make more bottom end power, but not the same top. I have a STRONG 250 motor now, but would like a better power spread. I DON'T want to lose topend, as I race desert, and need the boost for the starts and just plain fast stuff. Who knows what about this?

[250rpilot]

give esr a call, at 559-625-3157. tell them what you want as far as your powerband goes, and they will hook you up.

[dawnchris]

I know they SAY what there stuff does, I'm looking for some concrete proof. My current 250 combo will pull away from the 310's i race against. I want comperable top end, but with more overall power.

[250rpilot]

there are some very knowledgable 250r engine folk on Rriders.com (http://www.rriders.com) most of them say the same thing though, esr all the way. you must have one hell of a 250!!:eek2:

[dawnchris]

Yea, it's a rocket alright. The problem is that it doesn't do the technical stuff well, as it's all topend. I'de like a similiar topend, but more down low. I think I could get it from a powervalve cyl. just don't want to spend that much.

[Chanman420q]

maybe try diffrant gearing?

[dawnchris]

Been there. I desert race, we go from super technical rocky,loose 1st gear hillclimbs, to 80mph sections across valleys. You gear down for the hills, and get passed on the long sections. Gearing doesn't fix powerband issues, it just increases RPM at a specific speed. I want the bike to have more power OFF the pipe, where it is more controllable. A broader spread of power would let it pull up the hills with the taller gearing.

[hondafox440]

High compression and/or a PV cylinder will help that..

[dawnchris]

18cc dome in head- can't get much higher. As stated above, don't want to spend PV kinda money.
How about some 310 input ?????????

[Chanman420q]

maybe the pv425 motor chef had in his R... im sure that would be nice. but again thats gunna cost more than the pv310

id say just suck it up and get the ESR PowerValve engine. the PV is gunna make the world of diffrance, ull get more power from bottom to top.

[dawnchris]

Well, so far, you guys have been pretty worthless. Try looking at the SUBJECT of this topic. "Opinions on TRX 310 power?"
I don't give a crap about what you think of a PV, or what I can do to change my current combo. I want to hear from someone who knows something about 310's. I'm interested in a 310 for a particular reason. If you have no input on a 310, shut yur friggin pie hole.

[ESR250R]

i think if you drive your 250 off a cliff that should solve your problem.

[INFANTRY RACING]

Originally posted by ESR250R
i think if you drive your 250 off a cliff that should solve your problem. you should do the world a favor and follow right behind him:rolleyes:

[AndrewRRR]

Talk to 310Rduner. He has a ESR 310 non-PV motor.
They make more power everywhere in the powerband typically (if you get it ported right). If you don't have displacemnt limits you should buy the biggest motor you can afford. a 330 can be turned into a 350 (or bigger) later with a stroker crank.
For what it sounds like you do, technical sections to wide open flat out sections I think you would be best served by a PV motor, there's just no way around it. Thats what people were trying to tell you. My 350 has lots of bottom still, but a PV 350 will whoop me in technical sections. The PV 310 is like $600 more which sounds bad but might as well save up longer and do it right.

If you do a non-PV motor, ESR's "bolt-on" 330 kit is only $50 more than the 310. I'm not sure about reliability with those however, since the sleeve doesn't portrude into the cases. Don't know if I'd risk it with desert racing.

[rollie]

talk to atkins450 hes not on here much hes on hbomb alot he has one and its crazy!:blah:

[InsAyneROostin]

Dude just effing chill for a sec. Listen to what people have to say. Go to LRD and talk to them about their 310 kit or whatever they have. have an open mind. don't call someone worthless because they're telling you how to go around something the right way. just my two cents. Peace.:huh :huh

[dawnchris]

If I was buckin up for a new cylinder, I WOULD go for the powervalve. The reason I'm wanting to know about a 310, is somebody owes me money, and is offering a cylinder in trade. I'm trying to decide if I should take it, or just wait for the money.
Therefore, the only input that does me ANY good is feedback on a 310 cylinder. Thanks to the guys that DID offer up some 310 advice.

[airheadedduner]

As long as its not a CT cylinder then it should be fine. It will be an improvement across the whole power curve. But if your 250 beats 310's then why bother? If you do get it keep the 250 cylinder and decide afterwards which one you like better. You can always turn it around and sell it.

[dawnchris]

Thanks for the input, I'll be keeping the 250 cylinder for sure. I'm hoping the 310 with some port work, will have the same topend the 250 has, but with more low/mid. I don't need much low, just a strong mid, before it gets up on the pipe.
It's a Pro-X cylinder.

[AndrewRRR]

Originally posted by dawnchris
Thanks for the input, I'll be keeping the 250 cylinder for sure. I'm hoping the 310 with some port work, will have the same topend the 250 has, but with more low/mid. I don't need much low, just a strong mid, before it gets up on the pipe.
It's a Pro-X cylinder.

What's done to it now, is it ported? The reason I ask is if it has a bad job, sometimes they can be salvaged and sometimes they can't. If it's got a topend port and you want bottom you are pretty much screwed.

[dawnchris]

He says it has an "all around" port job. Set up for recreational power. He owes me $225, and wants to trade the cyl., head, spacerplate, new o-rings, and new rings. It's currently .020 over. Said the piston has some scuffs where the last place that bored it didn't relieve the exhaust bridge area.

[wilkin250r]

A 310 "all around" port job will have about the same peak HP as a 250 ported for all top-end, but the 310 will have much more bottom end-power.

With the larger piston on the 310, it may not want to spin-up as fast, but you can help that out with a lightened flywheel.

All this is assuming the port work is of comparable quality. In reality, much of it comes down to the port work involved, so it truly is a huge gamble. Not all port work is equal, I've seen 250 engines with excellent port work that will run circles around 310 engines, even when both of them have the same "midrange" porting.

[dawnchris]

My thoughts exactly. I'll give the jug a try, if it sucks, I'll just sell it. I figure I should be able to get what he owes me out of it. If it rocks, then all the better. Thanks again.
By the way, what do you think of that Duncan PV? You don't see too many of them, so I ask when I can.

[wilkin250r]

Originally posted by dawnchris
My thoughts exactly. I'll give the jug a try, if it sucks, I'll just sell it. I figure I should be able to get what he owes me out of it. If it rocks, then all the better. Thanks again.
By the way, what do you think of that Duncan PV? You don't see too many of them, so I ask when I can.

I'll give you the good news first.

When I got my 250r, the motor was basically stock, with an aftermarket pipe. When my girlfriend and I would race on asphalt, I could jump off the line a little quicker, but then we were dead even through 5th gear, and I had to shift into 6th gear to pull away.

When I put the 340PV, I changed the gearing way down (from 13/38 to 14/36) and I still had better acceleration than her, and the powerband was really smooth. In fact, it was difficult to judge my speed, because the powerband felt so different. The only way to get an accurate measurement of the change was to race my girlfriend again.

I remember one race in particular, on the same road we always raced on, I was taking it easy, staying right with her and counting her shifts. She was WOT, and had just shifted into 5th gear, and I was 1/2 throttle in 3rd. I pinned the throttle, and pulled away like she was standing still, so obviously even with the gearing change I had a big increase in both acceleration and top speed.

The bad news? I bought the motor complete, and it had a vibration problem. It may not have anything to do with Duncan Racing. Then again, I talked with another guy with the same top end, and he developed a vibration problem from excessive wear on the crank. (I'm not sure what my problem is, I need to send it out to get rebuilt) It may be that this top end is hard on the crank. Then again, it may not be related to the top end at all.

[AndrewRRR]

Originally posted by wilkin250r

The bad news? I bought the motor complete, and it had a vibration problem. It may not have anything to do with Duncan Racing. Then again, I talked with another guy with the same top end, and he developed a vibration problem from excessive wear on the crank. (I'm not sure what my problem is, I need to send it out to get rebuilt) It may be that this top end is hard on the crank. Then again, it may not be related to the top end at all.

Wilkin I'd definately check the crank out. When I tore down my 350 (it has an ESR 4mm long rod crank) it was 8 thousandths out of true and spun the counterbalancer. When you have it apart get the crank trued and welded, and go to the long rod if you have an 86 length rod. These big R motors are hard on cranks.

[Bean]

bigger piston = bigger vibes, unlesss it is shaken your teeth out, then it could be your crank out of ballence, or something else in the bottom end

[cuffhim]

I've got two 87 250R's. I've run an ESR 310 on one of them along with V-Force reeds and a ESR pipe. It runs really strong. I just purchased a CT Racing 310 Cylander from "DFR" and took it out for it's first break in run. I will tell you that, without really getting on it, the thing screams. It honestly seems faster and more responsive then the ESR. It too has a set of V-Force's with a Paul Turner Pipe. I run a 38mm carb on both bikes. I recenlty blew the ESR 310 and it is now being rebuilt by Rudy Gonzales at DFR. He is not the person that I purchased it from. I've learned a lot about these darn 310's in the last few weeks. First, much of the criticism toward CT is now unwarranted because it appears they have changed their porting on the LA Sleeve Pro X cylander. It really does perform extremely well, both at the top end and the bottom. I run 13-39 gears for the MX track. I run 100% VP gas (110 Octane) with a 40-1 mixture of Power Plus synthetic mix. This is a much better set up than the half pump gas, half race gas mixture I ran on the ESR. I also used to run the Power Plus at 50-1, as the manufacturer suggests. I am sure my fuel combination and fuel oil mix contributed to the ESR 310 taking a dump. I place complete trust in Rudy and will be following his advice on both new cylanders. By the way, the compresion on my CT 310 is about 205 lbs. Pretty good. I'll post again when the ESR 310 comes back from LA Sleeve with a new sleeve. I'll let you know how it's performing as well as what the compression is. Good Gas + Proper mixture + Proper Gearing = reliability and performance, whether it's ESR or CT. Good luck! Long live the 2 Strokes.

[AndrewRRR]

Thats one of the problems, eventually you'll get fast CT port job and sometimes it'll be really mediocre. They know how to port, but maybe they have people other than Alan doing the porting.
I wouldn't ever run 50:1, the oil savings isn't worth the cost of a motor. I run castor oil at 32:1.

[dawnchris]

Thanks again for the good info guys. Hey Cuffhim, post again when you know more.

[airheadedduner]

Originally posted by cuffhim
First, much of the criticism toward CT is now unwarranted because it appears they have changed their porting on the LA Sleeve Pro X cylander.
Personal experiences, some people have good luck with CT, some people don't. It all comes down to your own impressions. Did DFR redo the CT cylinder or was it the CT porting?

Originally posted by airheadedduner
Personal experiences, some people have good luck with CT, some people don't. It all comes down to your own impressions. Did DFR redo the CT cylinder or was it the CT porting?

For the most part, the porting is all CT, I have received a few that needed some touch up work (in my opinion) but nothing major. I have had no bad luck with the CT cylinder kits, seems most of the complaints about lack of bottom end or top end are solved by properly jetting and gearing the machines.

[airheadedduner]

The CT 310 I rode was set up for mx with 38 A/S, LRD pipe, K&N, LRD high rev cdi, and stock gearing. I am not sure on compression but he(not my bike) was told to run 108 in it. Throttle response was crisp, didn't fual plugs, ran great, and would get beat by a piped shee:( Shee had T'5s, vito's degree key, and K&N. My friends 88' PTR ported R with LRD pipe and K&N with milled head beats the same shee by about 2 bike lenghts, he runs stock rear sproket with 14 tooth countershaft sproket. After that bike and a couple other CT bikes I have rode including my own 295R I will not run there ported cylinders. Lack of bottom end wasn't the issue I had on my 295 or the 2 310's I have ridden by them, they did not rev out and felt flat on top. THey didn't pull from the mid like I thought they should have either. Like I said though, its all preferance, for the price there kits are a nice bolt on.

[wilkin250r]

Originally posted by AndrewRRR
Wilkin I'd definately check the crank out. When I tore down my 350 (it has an ESR 4mm long rod crank) it was 8 thousandths out of true and spun the counterbalancer. When you have it apart get the crank trued and welded, and go to the long rod if you have an 86 length rod. These big R motors are hard on cranks.

I think I'll just buy a new crank, and have the crank also ballanced against the larger piston. It's more expensive, but it should reduce the vibration from the larger piston, as well as reduce the stresses on on the crank and prolong the life of the crank. I didn't know balancing the crank was an option, but somebody clued me in a few weeks ago, and now I'm glad that I waited to rebuild. It still may be a while before I get it done, but when I do I'll let you know the results.

[cuffhim]

OK, the CT 310 finally saw a race. Rudy at DFR set it up and my son raced it in the Intermediate class this past weekend. I ran a 175 jet, a 38 mm carb and a 14-39 sprocket set-up. He raced all Yami 450's. He got one holeshot and ended up in second place. He had every bit the acceleration, high end power and low end torque of the other bikes. The 310 is every bit the bike the Yami is. Only real down fall is the extra gear makes the bike a little more work. As 2 stokes MX bikes go, the CT310 did well by us. Before you Yami guys pound me in your replies, know that I love the Yami and will eventually get one. Just givin props to the 310 cylander.

[dawnchris]

Good to here.