Thumper Racing 280 Big Bore kit Long Term Experience?

I would be interested in hearing from owners that have serious mileage/time on their Thumper Racing 280 big bore kitted engine regards: reliability, oil consumption, vibration, issues and overall experience etc...


thanks!

No takers on this? I am curious as well.

From what I have seen on other posts, the 280 kit is superior (and cheaper) than the 290 kit. The goal of the 280 kit to keep the vibs down likely helps a lot with the big bore kit not decreasing reliablilty / longevity. But I don't have firsthand experience! Someone chime in!

Some info here......

http://www.supermotojunkie.com/showthread.php?126567-Thoughts-on-big-bore-kits-for-the-wr250x....

What am I going to do..... enjoy the bike and if I want more HP buy a new bike but the maintenance schedule scares the hell out of me

Carmmond wrote:

Some info here......

http://www.supermotojunkie.com/showthread.php?126567-Thoughts-on-big-bore-kits-for-the-wr250x....

What am I going to do..... enjoy the bike and if I want more HP buy a new bike but the maintenance schedule scares the hell out of me

Honestly I didn't get much out of that other than it seems like the thumper racing one would last a bit longer because it had more piston rings. But that one guy seemed to have had his athena for a few years and was still going strong.

Jumping this bike up to a 280/290 would probably be perfect if you ask me, the Husky 310 is an awesome bike, and the displacement is a big reason for it. In regards your comment on maintenance schedule, I am assuming you mean other bikes. Having a WR450 I tried to DS, you did have to change the oil a LOT.

[quote="YamaFling"]

Carmmond wrote:

Some info here......

http://www.supermotojunkie.com/showthread.php?126567-Thoughts-on-big-bore-kits-for-the-wr250x....

Honestly I didn't get much out of that

Just posting a link to some people running them.... you have to do the work and talk to them

Any long term use reports of the Thumper Racing 280 Kit? I've got one in the box, but would like to know other riders experience with the kit before proceeding.

I've been running TR stuff for a while in my bored & stroked KTM & trust Travis. One thing you need to keep in mind on internet reviews is you will always see the negatives posted, the positives not so much. Since I have never found a negative on the WRR/X TR 306 kits, I bought one ;)
I would no hesitate to install the kit, the only regrets I found were people that wished they would have put them in sooner. Expect a similar boost to uncorking, it ain't gointg to be a 450 ever..

Since I have never found a negative on the WRR/X TR 306 kits, I bought one ;)

4Play, have you installed it yet? If so, how's the low to midrange power? I'd like to get similar low - midrange power to the XR250R's.

John

No, picking it up now. I did see the dyno sheet on the 280 kit. 43% improvement in torque at 5k over dead stock so the airbox and header gains are included in that. The performance gains mirror the 290 Athena without the increase in vibration that most 290 users report. Everyone reports low and mid gains and the ability to pull 6th better in a headwind

Default the results are in



We finished the dyno runs today. What a deal I left at 4am to drive to Vegas for the run and drove back to LA right afterwards. 9 hours of driving yuck. I did find out some real HP#'s from the guys at DynaJet and they were kind enough to give us an overlay of a stocker, the GYRT kit and the thumper Racing kit. I know different Dynos will give different readings but all 3 runs were taken on the same dyno with the differences noted. We now have maps for both the PC3 and PC5's available.

The ThumperRacing kit made the most peak HP +.75hp and maintained a 1-2 hp advantage from 9k to redline. If you look closely you'll see on the dyno chart for the GYRT kit it looks like Yamaha lowered the redline by 500rpm. There is a slight dip in HP and Tq from 6500 to 8800rpms. This is due to the powerbomb header. Using the stock header would have improved this area and we would have run at or above the GYRT through here as well. I didn't bring the stock header with me or I would have gotten a run with it as well.

All in all I'm very happy with the results. We are giving up 15cc to the GYRT and are still making more power.



It's interesting to note the ambient temp between the 3 runs is was stock 61deg, GYRT 82deg and ThumperRacing 95. Barometric pressure was all about 28 in-Hg and humidity was 13% for the GYRT and Thumper, stock run was 28%. We still made more power even though temperatures were highest during our test. We would have made another .5 hp if we tested with the GYRT at 82deg and about 1 hp if we could have tested with the stocker at 61 deg.

Mods:
Stock bike --well stock
Athena/GYRT kit-- GYRT exhaust, GYRT ECM, Athena/GYRT290 kit (289cc)
Thumper Racing-- Full FMF PowerBomb, PC5, Thumper Racing 280 kit (275cc)[/quote]
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Who made the trip to Las Vegas to do the dyno runs with the TR 280 kit? Are the HP/TQ graphs available? So, the FMF powerbomb and FMF muffler reduced the midrange? It would be interesting to find out if the cause was purely mixture or due to the FMF muffler and/or powerbomb.

Sorry. my cut n paste from Supermotojunkie was not too well executed. That was Travis, the owner of Thumper Racing

I found the dyno chart\\



Nice bottom end boost

Travis recommended I stay with the stock header for 280 & bigger motors based on his dyno work with the 280 & 306.
I bought the R2 with the intent of installing the 280 kit, but a member here had a bargain on a 306 kit he never got around to installing. I should have time to do it in a few months.

Thanks for the graphs 4Play -- there's nothing like a picture! Really big gains in the 4-6k rpm range with the 280 kit -- I would have liked to see a dyno run with everything stock except the 280 kit to see how much the intake and exhaust mods contributed.

As choked as the stock motor is by the intake & exhaust I would expect the torque graph to move ~1000rpm to the left just like this graph shows but with very little peak HP gain. Just uncorking/tuning has been documented as 4-6hp gains, going from ~21 stock to ~26 RWHP. I just experienced that on mine, I've never owned a bike that opening the air box, a muffler & tuning made that dramatic a difference in the way it rode. Once you've done the uncorking, the next step is pretty reasonable...

I guess that's the next step then for me. Mine's completely stock except for a powerbomb header.