Thumper Racing is developing a 310/320 kit?

It's October and no big bore kit! ughhh! In supermotojunkie link click me (2/3 down the first page) one of the members received a email from thumper racing that it should be done in September.

I would love to get a hold of this kit for my bike.

If the Athena 290 has more vibes than stock or even the TT280, I can't image how bad they would be in a 310/320 kit. Then, there's that reliability thing...

I can deal with some vibes if I get power without much hit to reliability. The fact that the turbo bikes are holding up pretty well makes me think the rod and crank are sturdy enough to go largely unaffected. I will definitely be looking in to one of these kits when I put enough miles on her to need rings.

Jäger wrote:

I think you bought the wrong motorcycle to begin with.

Just because I wouldn't mind buying a big bore kit for the bike? I am not trying to make it into something that is not, like trying to make it similar to a drz. If i wanted something like a drz i would have bought it already since the prices are pretty much the same and would be an easy swap. I've never complained about the power of the wr250 and the bike is everything I expected. That's like saying for people who put an exhaust, fuel managemnt system, mods, that they bought the wrong bike since it is not in stock form and they would like more power.

I think it would be a fun project to do and more power is always a big benefit. I would have bought the thumper 280 kit, but why buy that now when the 310 seems not too far away?

Everything can always be better

Like I said though, I wouldn't spend the money to do it to my fresh engine, but if I am having to tear in to the thing and rebuild it at some point, might as well spend a lil extra to get a little extra. 320ccs would probably produce about 35hp from an uncorked and properly tuned engine right?

BoredAzHell20 wrote:

I think it would be a fun project to do and more power is always a big benefit. I would have bought the thumper 280 kit, but why buy that now when the 310 seems not too far away?

I think the 280 kit would be the biggest I would go for a bit more power and keeping the reliability relatively the same. I was actually thinking about installing it this winter. But then decided that my bike runs so well that I don't want to mess with anything until I have to.

When and/or if the kit comes out, by all means install it if you want it. I would be anxious to hear your impressions with it installed.

Which would be more "stressful" for the wr?

Turbo kit

or

Big Bore Kit

My "guess" would be that at equal power levels they would be pretty close in reliability so long as the piston for the big bore is a good design. The turbo of course has the ability to go much higher though and then it will be harder on the motor.

trav72 wrote:

BoredAzHell20 wrote:

I think it would be a fun project to do and more power is always a big benefit. I would have bought the thumper 280 kit, but why buy that now when the 310 seems not too far away?

I think the 280 kit would be the biggest I would go for a bit more power and keeping the reliability relatively the same. I was actually thinking about installing it this winter. But then decided that my bike runs so well that I don't want to mess with anything until I have to.

When and/or if the kit comes out, by all means install it if you want it. I would be anxious to hear your impressions with it installed.

You got it. That's if they even make it.

If they didn't initially make the 290 BB kit due to vibration issues due to the heavier piston when they produced the 280 BB kit, I wonder what they are going to do to the 310 kit to not have the same issues

Quote :

If they didn't initially make the 290 BB kit due to vibration issues due to the heavier piston when they produced the 280 BB kit, I wonder what they are going to do to the 310 kit to not have the same issues

Light-weight Kryptonite pistons

can they go that big without messing with the combustion chamber? alsl wouldnt it need port work to breathe.

if properly tuned the turbo will be easier on the motor. the big bore changes the rotating mass and throws off the crank balance (as indicated by the increased vibes).

I will be getting the first 310 kit. Earlier this year I responded to a request from Thumper Racing for a stock cylinder to do some R&D on for the new kit. Since I had just done the 290 upgrade, I had a spare cylinder and sent it to them.

They're still working on it. The new kit will have +3mm bore and +3mm stroke. Last time I exchanged emails with them they said that they were still trying to reduce vibrations, so the kit's not ready yet.

I'll post up when I hear anything new.

[quote="BoredAzHell20"]

trav72 wrote:

If they didn't initially make the 290 BB kit due to vibration issues due to the heavier piston when they produced the 280 BB kit, I wonder what they are going to do to the 310 kit to not have the same issues

The new piston is actually lighter than the stocker. Vibration in the new kit is due to increased stroke.

Jäger wrote:

I think you bought the wrong motorcycle to begin with.

They were fresh out of WR350Rs when I went to get my perfect bike.
As much as I would like something like this, I'm not very interested in splitting the cases to drop in a new crank.

And then there's this.
http://www.ktm.com/at/news-events/news/alle/details/news/detail/News/a-new-and-very-light-start-ktm-freeride-350.html
I hate those orange bastards.

skidmarx wrote:

Jäger wrote:

I think you bought the wrong motorcycle to begin with.

They were fresh out of WR350Rs when I went to get my perfect bike.
As much as I would like something like this, I'm not very interested in splitting the cases to drop in a new crank.

My perfect bike would be the Aprillia 5.5 supermoto with the maintenance intervals and reliability of my WR250X.
For getting dirty the WR250R is fine for me.

I would go for a sorted 310 kit (reliable and no extra vibration) when my WR250X needs a rebuild. My guess is in 2025.
I only put about 5K km a year on my WR, the Strumpet gets over 10K km a year.

skidmarx wrote:

And then there's this.
http://www.ktm.com/at/news-events/news/alle/details/news/detail/News/a-new-and-very-light-start-ktm-freeride-350.html

Only 24 HP? I'd expect well over 30 HP from that...

[quote="BuilderBob"]

BoredAzHell20 wrote:

trav72 wrote:

If they didn't initially make the 290 BB kit due to vibration issues due to the heavier piston when they produced the 280 BB kit, I wonder what they are going to do to the 310 kit to not have the same issues

The new piston is actually lighter than the stocker. Vibration in the new kit is due to increased stroke.

Are they going to offer that new lighter than stock piston as just a big bore kit, sans stroker crank?

skidmarx wrote:

deerHater wrote:

I would go for a sorted 310 kit (reliable and no extra vibration) when my WR250X needs a rebuild. My guess is in 2025.

Only 24 HP? I'd expect well over 30 HP from that...

That's funny. I was going to post that I wouldn't mind doing the 310 when my bike needs a major overhaul, but the way these things run, that would be about...never.

I think 24hp is so ridiculously low for a 350 that I'm going to ignore it.
Maybe they have it breathing through cocktail straws.
My XT350 has more than that and it's air cooled and designed in the '80s

217lbs though. Assuming you can get it to 35hp, which seems reasonable, it would be a quick little machine... assuming you are a lighter rider lol. Boy I wish I weighed 150lbs.

BuilderBob wrote:

I will be getting the first 310 kit. Earlier this year I responded to a request from Thumper Racing for a stock cylinder to do some R&D on for the new kit. Since I had just done the 290 upgrade, I had a spare cylinder and sent it to them.

They're still working on it. The new kit will have +3mm bore and +3mm stroke. Last time I exchanged emails with them they said that they were still trying to reduce vibrations, so the kit's not ready yet.

I'll post up when I hear anything new.

That's pretty cool. How long did they had your cylinder? Anxious to hear your input on the 310 bore kit once it is all done, since your going from the 290 to 310.

Awesome stuff man. I hope it works out good for you.

BoredAzHell20 wrote:

That's pretty cool. How long did they had your cylinder? Anxious to hear your input on the 310 bore kit once it is all done, since your going from the 290 to 310.

Awesome stuff man. I hope it works out good for you.

I sent it to them in June I think. I try not to pester them as I know it takes time to work these things out. I'll probably check in with them sometime next month.

It's been a while... any news on this front?

Arkmage wrote:

It's been a while... any news on this front?

Still nothing to report. They moved their shop from CA to NV this month and I think they're still trying to get caught up. I decided not to contact them during the chaos. My guess is that there won't be any news until after the Holidays.

Ok. After posting the above, I decided to contact Travis at Thumper Racing via PM. He got back to me right away.

I was right. The move has put them behind schedule. Now estimating January for finished product.

But before you get too excited, this is a stroker kit, which includes the crankshaft. You will have to split the cases to do the install.