TTR325 Review/Report





I started this project out of necessity ( I hated my 2006 WR250F) I sold it and dug my old TTR out of the back of the garage, now dont get me wrong this bike was CLAPPED OUT. I got it new in late 99 it was a new 2000 model, the frist ride and I knew it sucked on power, I was comming off a KTM 250EXC but had always rode XR250's before the EXC, and the bike was so down on power even by XR250 standards. so I did some research and found that Scott Summers offered a 280 kit for it and I put the White bro's E-series on it. now i had a bike I could race eastern style enduro and Hare Scrambles on. I am only 5'7" Tall and have had 3 knee operations in the past 15 yrs so the E-buttom was what I needed, that and the low seat height made it a perfect bike for me and I had to adapt it to a racing bike. I have raced this bike from the UP of Mich down to the GNCC in FLa and it always got me back to the truck, sometimes with a trophy and sometimes with a few bruses and scratches but all in all it got me back, after all the years of abuse and lack of proper care it was finsihed so I thought I needed the new fancy liquid cooled WR.(side note I bent the left rad on the first ride)

So the project began with the 325 kit. I have delt with Thumper Racing in the Past and knew they had a solid reputation for good long lasting products so I called them and got the kit. This kit comes with every thing you need. Sleeve, clutch springs, air filter and cage, piston, gaskets and a spark plug, ooh yea a main jett also. (TAKE MY ADVICE AND JUST SEND THEM YOUR MOTOR AND LET THEM DO IT, I CANT NOT STRESS THIS ENOUGHT) it will come back to you ready to bolt in the bike and go racing.



Next I took the bike completly apart and had the frame sand blasted and powder coated,


I replaced every bearing in the bike. new motor bolts, BNG and fenders. So now I am ready to go riding.

The power gains are better then expected ( I was looking for more hit off bottom for crossing logs and lofting the front tire in the air, it does this with ease and no effort from my weak arms) :thumbsup: I guess you can play with the gearing but I like it stock for what I do, I have no desire to go 80mph EVER... So if you have a TTR250 and have the same sick love affair with it that I do this is money well spent, This bike just fits me I guess, why would I have kept it so long, my friends still do not get it but I do beat most of them on it so they keep thier mouths shut most of the time.


Next I came across a complete 2003 YZ250F front end on e-bay I have less then $300 in it and being the kinda of guy who grew up in the hey day of moto in the 60's & 70's watching my dad and his friends fabricate parts to old Huskies I knew I could make it fit some how (note a person told me it would not work and would change the stearing angle, but I have put about 30 good tight trail miles on it and it works just fine, never say won't to a guy like me) anyway I got it and took the stock one off and slid the inverted forks and clamp up in the frame, it was about 1/4 inch longer then my stock steam, I just took the nut off my old one that has the slots in it for the locking spacer and used a drimmel tool and ground the threads off the inside of it until it fit smoothly over the extra steam on the new one,(The stock TTR has 2 of these nuts so it fig it is ok. It feels solid when riding)


then screwed the yz nut on top of it and put the locking spacer over this and slid the top clamp on and the top clamp nut presto it fit and there is no play in it at all. Now I always run my forks a little futher up in the clamps to shift the weight forword for better grip in the corners ( it aint like I am blasting threw a whoop section that often so high speed slap is not an issue for me, that and a good old fashion Scotts damper with let you go as fast as you want).

Am I happy with it? You freakin bet your butt I am. The smile factor is so high I am stoked about riding again, heck I went riding and it was in the high 80's and i usally par take of water sports when it gets this hot. So there it is my report of the improvements to my TTR. I hope it helps someone who is on the fence about making this mod to thier bike, You will not see a $$$ return on this, but if you like your bike and plan on keeping it for years go for it. If not then go out and buy a WR that you are going to hate and sell to a friend for a big time loss.:thumbsup:

OK lets go riding

Bryan Wedmore

If you want more details e-maile me at

I hope this is what you were looking for as far as a report goes? if not let me know ok.

Great write up!!! Might want to edit it and add a pic in there somewhere too!!!!

If you look threw the post on here you can see I have put photos up as I went, but you are right I posted the links to photos I tried to put the photos in but it would not do. so if anyone can do it (MOD"S?) feel free.

I went ahead and added the pictures instead of the links, I also added a pict of the front end bolts I talked about in the write up.

how much horsepower does the 325 big bore give you?

I have no idea but it made the bike a very fun woods weapon, like i said it lofts the wheel in the air with no rider input and barks out of corners it is perfect for me I know that.

You can cqall Thumper Racing and they can tell you.

what was it before it was a 325?

It was a 2000 TTR250 I got in late 1999.

nice lookin bike man

Excellent looking bike.

Great Work!

Did you do a full motor/gearbox strip down and rebuild? Or just the cylinder piston kit? And, did you have to do anything to the head to fit the bigger cylinder?



Why did this thread die? Excellent write up on the TTR. Awesome mods.

Giving an XR400 a run for the money! No, wait, beating it! Nice inverted forks!


nice looking bike, i have just bought a pair of 03 YZ250 forks and clamps, so have a bit of work to do to get them mounted etc.

i will post some pics up once it is all done, in the meantime if anyone has any tips for fitting it would be much appriciated!

I like the mods you made, especially the forks.

I have an '03 250 and I am not happy with the front end. Do you have any idea what other models fit besides the '03 YZ 250?

My plated 2005 Yamaha TT-R250 already has 2 stacked collars on it stock from Yamaha. Bolting on the YZ inverts seems like it should be an easy swap. I can't wait to get a set.



Nice looking bike MrFlaky! How tough was it to install the YZ forks? What year YZ forks did you use?





i beleive they are 2003 models, fitting wise not too bad, took about an hour and half to get all mounted up, plus the same again to do the new caliper bracket.

went on no problems, apart from messing around with the front wheel to get it centered. Having never fitted a pair of forks before it was surprisingly painless.

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