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Found 49 results

  1. I found a Magnum 290 kit on ebay for my 09 yz250f; thought I'd give it a try. It was $400, figured that's not too bad for cylinder, piston, and gaskets. Advice #1: After you take your current piston off; put the new jug on with the water jacket dowel and the two steel dowels in place to make sure everything is going to fit right. Make sure the castings are perfect so it fits down nicely and flat. Mine were a bit too tight in one spot, and I had to dremel just a tiny bit off a steel dowel hole edge for a good fit. Advice #2: Be super careful about stuff dropping into the motor, take your time, cover the motor very well. Advice #3: The four head bolts? they are different lengths, note which goes where. Advice #4: Put the exhaust cam on first, then the intake. Advice #5: Measure your valve clearances as you take your motor apart. Otherwise you have to put it together again, just to see you would rather have shimmed. Advice #6: Put those metal clips into the cam caps, then put the cams into the caps (carefully getting the cams into the clip properly), then hold the cams as you put them in the head Power does seem to be increased everywhere. It's a noticeable increase. I had heard that it signs off hardcore up top; maybe I didn't rev the crap out of it because it was the break-in ride, but I didn't feel that. Is it a mini 450? Is it a 450 slayer? No, I mean, in the right hands it could be; but a 450 is still faster and even if you can be even with them for a stretch, then you have to shift. Mine doesn't feel as fast as a Husqvarna 350. It feels like a strong 250f, but still a 250f. Maybe now you can be one gear tall coming out of a corner, but not almost any gear tall like on a 450. The increase is noticeable and welcome though. It felt strong and I liked how it ran. I recommend this kit, it felt great.
  2. Sunflash

    RTW 470

    So I have done lots of searching but can't seem to turn up the info I am looking for. So after a 25,000 mile run from Deadhorse, AK to Yaviza, Panama and back to my home in Alaska on a Rally Raid Level 3 CB500X..... I am now going back to my roots and picked up a 2004 DRZ 400 with about 2900 miles on it. Lots of reasons for it but the cut it short I know I was looking for something different for the rest of the ride around the globe. So my plan is to build a bombproof DRZ that can take me everywhere and back. To that effect I have already ordered an Athena 440 kit, will be going with the Hotrods +4mm crank kit, and the ACT wide ratio gears. Where my plan differs from most of the other power mongers is that I want to keep the compression low enough to run low regular fuel without going nuclear. That type of tuning runs a bit contrary to everything I can find info on. So who out there has done a low comp 470? Since the plan is a mild state of tune rather than the usual fire breather everyone else is trying to build does anyone have a good recipe for the spacer or gaskets to keep the compression low enough? Cams for the milder state of tune? FCR 39 going to be enough carb or should I be looking to the 41? My engine building has been limited to old air-cooled 4 cylinders and for max grunt not longevity on crap fuel. Lots more will be done to the bike but the motor spec is one of the ones leaving me a little out in the cold. Want the grunt of a bigger motor to pull the wide gears but not the short life of a rocket ship. Thanks for the help.
  3. Friend has a 2014 ajp Pr3 which has an electric start zongshen 233 cc 5 speed engine in it,he loves itespecially the low seat height for his short stature. Only bitch is its slow as hell. Can he use top end performance honda crf230 topend parts,or rev box,carb,??? No room for bigger carb i am told as gas tank is behind engine. I have not seen bike as he lives 200 miles away,but would like to speed it up over winter[Northern Vermont winters are verrry long] Any input or info would be greatly appreciated.
  4. Greets to all. I'm about to install an Athena BB kit on my S. Kit comes with a single layer base gasket an gives 12.3:1 compression ratio. I've been thinking about bumping up the compression a bit. No budget available for a hi-comp piston, so I was thinking of machining the cylinder face down a couple of tenths of a millimeter. I have access to machinery needed for the task, so cost is out of the question. Will check piston-to-deck height and all before proceeding. My main concern is the nikasil coating, actually the point it "finishes" at the top of the bore. There's a chamfer right there, measures over half a mm high, so could easily be ok. But I need confirmation, wouldn't want to ruin my BB. Anyone done that before? Any problems with it? Thanks in advance. Lefteris.
  5. Hello everyone, I've been away from the forum for a bit, after I ran the DRZ into the ground and couldn't fix it until now. I've read through many posts about big bores, but most of them are aimed at max HP and things like that. I'm not looking to make 55HP, but my engine is done so it needs everything. I ran the bike on the highway for too long, didn't check levels properly, vaporised all the oil and ruined the engine. The big end is gone, the cilinder wall is worn, the cams and chains are worn and even the valves are having issues. I ran it for a while with all these problems, since I had not other transport. Gotta love a bike on a budget.... For the last few weeks I've been looking for big bore kits and info on them. I want to build a DRZ that does a bit better on the highway, has more power overall but want it underpowered and overbuilt. Towards 50HP would be nice, but not a requirement. My budget is decent, but not endless, which gives me a problem: there are soooooo many brands and styles around, I can't see the forest through the trees. The prices differ immensely, as does quality. On top of that there are setups that just run on race gas, which I can't over here, so I'm looking for a streetable setup. Since I live in the Netherlands, Europe, I have to ship everything over, and to save money in the long run I would rather spend a bit more initially and get it right, instead of getting three different kits. Its a 2005 SM with a stock engine, I will get: Big Bore cilinder (not set on cc's, but looking around the 470 range) Piston Stroker crank/rod (crank is most likely done) Cams (don't need super hectic lift and duration) ACT gears Carb (39 or 41) All the consumables and bearings Its fitted with a Leovinci 3X, have the 3x3 mod, valve and other smog stuff is removed. Not a brand fanboy specifically, I've looked at and could find out about them: MaxRPM, both IceCube and the Stealth, looks great but pricey. CilinderWorks, not sure what their quality is but they're cheap. Athena, mixed reviews and medium pricing. HotRods cranks, famous name but no idea on durability. HotCams & Web Cams, I don't have a preference, whichever gets me the best cam. And a bunch of brandless cilinders, packaged with branded items. Impossible to find out what the level of quality is. Who can help me out on deciding on this setup? More top speed, more power over the whole range, but rather have less power and more reliability than maximum RPM. I know the best solution is OEM, but since I'm building it, I might as well add to it.
  6. What can I expect as challenges to using the bigger fin cylinder from a ATC200X on a TLR200 Reflex engine. I want the extra cooling from the bigger fins. Am I going to have to also use the ATC 200X head and then use the ATC200X ignition parts? Help me if you have done this by telling me of your experience mating these to a Reflex TLR200. Thanks, Croatan AKA Tim
  7. Hello Chaps Nick from England here. First post so go easy on me :-) i wonder if if anyone can offer views on feasibility of increasing the capacity of a Chinese Suzuki GN125 derived engine beyond the "big bore" limit of 147cc. Following the advice found on this forum I've fitted a Chinese 147cc big bore kit, a VM26 carb and a DR200 cam...actually a Chinese QM200 cam, but I'm told they are the same thing. This is nice, but I would like to increase the capacity further, ideally up to 200cc. I know the stroke is longer and bore is wider on a 200cc variant so im guessing I would need a DR200 crankshaft, con rod, piston, barrel and head. But, in big handfuls, is this likely to be compatible with the 125 crank case and transmission ? ive posted here because there are (or were a decade ago) some guys who seemed to know everything about swapping bits between the small two valve Suzuki engines. Whereas other forums tell me I can get major performance increases by changing the air filter and spark plug :-) Thanks in advance Nick
  8. I recently brought my ancient '00 DRZ-S back to life. Had been collecting spiders for a good 10 years, but I managed to get her running and even rode a bit before she broke. I'm 90% sure the head gasket went, as white smoke was pouring out of everywhere and wont start now. While she was in her heyday, I got a Yosh pipe, FCR 39, and a handful of other mods put in, but never went big bore. Now i'm ready. I'm fairly good at wrenching, and in no need to complete this in a weekend or two. To set the stage, she's setup for street with SM wheels and larger brake disc up front, but stock caliper. I commute about 80miles a day in LA traffic, so anywhere from 10 to 85mph. Looking for recommendations, I know I want a big bore upgrade, and new crank, probably upgraded valves as well, I'm sure there is more. I've got some cash for the project, so no need to try an do it on the cheap, but I would like to do it on my own (i'm a masochist and enjoy that shit). Would also like to upgrade those brakes, I need moar stopping power, maybe a new caliper, idk. Thanks MotoDad
  9. I recently installed a 165cc tb big bore on my 2007 klx110 and also the 28mm carb the bike bogs super bad when you give it about 3/4 throttle any advice on what size jets I should run would be great if you need additional info I’ll gladly reply thanks in advance. Or if not jets what else could be the problem.
  10. I have a drz400s with a +4mm stroker kit. I was running a 4 layer base gasket to lower the compression bit ended up blowing a head gasket anyway from not tightening down the head enough ( did the 34.5 from the factory manual saw on here it was supposed to be 43). Now when the head gasket blew the head warped slightly so I got it resurfaced. When I got it resurfaced the machinest said he had to take .07 inches off which seems like a lot to me. Now with a stroker and that reduction in clearance I'm worried about where the compression ratio is. Has anyone in a similar situation got any insight? Should I be alright with a 4 layer base gasket or am I sitting on a ticking time bomb. Thanks.
  11. Hey everybody, first post after years of lurking. Saturday I traded my johnboat for another bike. A very rough 2006 ttr125 with a 150 big bore kit. (no idea who made the kit). She starts first kick no matter what, idles and runs great until about 7/8 to full throttle where it proceeds to fall on its face until I let up. Bike has an "aftermarket" carb that i'm having trouble identifying. The only marking on it is an "M" cast on the side of the body. the insides look brand new but the jets dont have sizes on them. I can post pics as soon as I get off work but without knowing what size jets I have i'm not sure what kit to purchase. Starting to think a new mikuni would be the best course of action. Any Ideas or discussion would be great. Thanks a ton in advance. -Ricky
  12. My '05 SM had it's rod bearing go out at 15,000 miles and scored my cylinder so its time for a rebuild. I already have the engine out and cases split, just getting ready to clean and inspect everything and spend lots of money. Bike as of now has 3x3, full Yosh RS3 Off-Road exhaust, and JD jet kit. The plan so far is to get: Hot Rods Crank Assembly Cylinder Works Big Bore Kit Cam Chain MCCT FCR 39 (hey why not) My main question is if I should replace the engine bearings or not. I feel like I should since I have the engine apart and plan not to have it again for a while, but its around $200 for main, transmission, counter balance, etc. I could not find anything about inspecting bearings aside from feeling smoothness. Is there anything that indicates I should replace bearings? Should they be fine? Or dont risk it and replace all since I had metal running through the oil? Let me know what you think along with any recommendations for the build. I plan on skipping out on the stroker to eliminate challenges with compression and reliability and skip out on cams for the sake of $$$.
  13. I blew up my '14 drz S a few weeks ago. Started, and ran cold up to to redline one the highway. I know it was dumb. But i have since installed a big bore kit and stroker crank. I also had the head serviced with new SS valves and had it ported and polished at Fastheads. I was running the 3x3 mod, and a JD jet kit. Everything else stock. Wondering if the bike will run well with stock carb and pipe, and what jetting to use. If it will run like crap, what carb and pipe do I want to run? (I want a quiet pipe) Normal operation is at 600 ft and cool, but do travel to colorado often.
  14. I have a 2012 ktm 350 sxf with a cylinder work big bore in it looking to get a fuel tuner wonder if I should go the the jd jetting tuner or the wisco. Looking around those price range
  15. Hello My son's klx110 is running rough. It has a 143cc big bore kit...also has the bigger carb after the big bore kit was put on. Ran great. After that the big bore froze up. We put on a new big bore kit with the upgraded race head. Since then I have had an issue dialing in the carb. I have tried moving the clip and everything. A mechanic got it as close as he could...also tried different jets but would only run well without the air filter on. At one point it ran really well but at idle if you gave it some gas it would bog down....not sure what the setting were at that point. Do I need a bigger carb? If so, which one? Any other advice or recommendations? Thanks
  16. Run 1 is a 2013 Drz400sm with 3x3 mod, FCR carb, and yoshi exhaust. (32.45 HP) Run 6 is my personal bike 2006 Drz400s (64.66 HP) -Myers Racing 94mm big bore kit -Myers Racing +4mm stroker crank -Myers Racing stage 3+ Cylinder head (Moldstar90 valve seats, Bronze valve guides, Stage 3 port) -Web cam (MR grind) -Ferrea valves (+1mm all 4) -Isotropic treatment on transmission -43.5mm FCR carb -K&N filter
  17. Alright good news. Had saved up a bunch of money expecting to owe a significant amount for taxes.. Turns out I don't owe nearly as much!! Time to put the money to good use and build a nice performance motor for my drz. I am planning on doing a full 470 kit from ebay (Stage 2 cams, +4mm Crank, 94mm Piston/Jug) Has anybody else done this big of a displacement change? If so how bad will this hurt my reliability? I know it wont be nearly as reliable as stock, obviously.. just wanted to get a few opinions before I jump into ordering everything. Also, if I follow through with it I would be doing the MX39 carb swap. I am running a new Yoshi RS-2 full system, but will swap to MRD if it will make a significant difference. Thank you guys, Brad
  18. A-Mart gonna podium.. Zookie goes kaboom 3 turns from finish line. Poor bastard.
  19. I just picked up a 93 kx 250 traded my 125 since it need a piston no problem i thought so i went to find the piston size for it but mine is a big bored at 73.8mm i just don't know where to find the new piston i was told by the owner that i could just search 73.8 mm piston and buy any one but i highly doubt that so if anyone can point me in the right direction that would be great thanks. Posted some pic below to see if it helps.
  20. The kit is a lot more affordable for what you get compared to the bbr when you take in the specs on the bbr cam compared to stock IMO. with that being said has anyone ever bored out their 120cc big bore cylinder to say 136cc? Or what’s the safe limit you can take one to? I have full range use to a machine shop and have no problem doing it myself.
  21. My trusty 2004 CRF450R is finally ready for a complete rebuild. I bought the bike new, rode my then 2 year old son on it, now he rides it and rides it well. We would like to up the low to mid grunt. Any recommendations? ML
  22. I have purchased a DRZ400e electric start engine (less the cams and stator cover). I have a stroker crank and big bore kit coming (happy birthday to me). Given that we are going into winter this side of the world I though it might make a good project over the winter. This engine build thing is all new to me so I will have plenty of questions in the coming months I'm sure (I also have beers with a couple of old-timer engine builders of a Friday evening and have been receiving a fair amount of encouragement from both of them) . The first few questions that you, @Erik Marquez or @Noble might know the answers to: What sort of cams does a 462cc DRZ run? @ohiodrz400sm you use WEB 539's? for what characteristics? This is a road bike, not a race bike. Next question valves, standard size, Ferrea, Ferrea spring kit as well? to suite the performance/lift/duration of the cams?. I guess I need to find a reputable head shop here to fit the valves to the head. Going through the bottom of the engine is a must as well. Do I replace all bearings / seals as a matter of course, this motor is unknown to me so a replacement water pump and oil pump (at least have the oil pump apart to check for service specifications), replace plastic oil pump gears anything else I anyone can suggest? I am considering an ACT wide ratio gearset at the same time. I understand that RS Yoshi exhaust may be impeding the performance at the top end but I see the 38mm throttle body to be the bottle neck at the moment (as well as only 398cc). I have a RMZ450 throttle body to fit. It's 43.8mm including the butterfly - so probably about the same at an FCR 41 in total flow volume. I have just started to machine up an adaptor to fit the airboot on my current setup I'll fit this shortly to my current setup and see how it affects breathing. I'll probably go the velocity intake route on the big build as well. Clutch - standard with new components - fibers / springs? I consider the motor in the bike have too low km's to mess with. In the meantime I can still ride on what I have.
  23. hi. i purchased GET athena WIFI-COM for Honda CRF250r 2014 ... to modify my stock ecu. my bike has athena 280cc bigbore kit with Pro circuit Ti-6 Titanium Dual System. need some suggestions what to change on the mapping that i dont damage my engine or something.. tnx
  24. I know the throttle body is 38mm (2mm up from 2016) also a revised air-box, reshaped air boot, new muffler design and a larger-diameter exhaust head pipe. my question is can you install a big bore kit on this? i haven't seen anything stating that it will work for the 2017 model (my guess is it will but i'm not an engineer). Thanks for the help.
  25. Hello fellow big bore lovers...... If you have ANY information (good or bad) please advise as it may either help me save from making a $4000 mistake or spend it and be happy. I have a line on purchasing two KTM 550 MXC bikes in Colorado. I have not seen them yet in person. I've talked with the owner twice and this is what I DO know. He is an ex pro hill climb racer and raced AMA, NHA and others. I will try to post photos. One is I believe a stock 1994 in very very nice original condition and the other is a 1995 model that was his race bike. The stock bike has had a Nikisil coating and I'm being told it runs very well and pulls super strong. The '95 model was highly maintained but was raced. No engine work ever performed. It has custom bolt on swingarm extenders that are easily removable so the bike can go back to stock. Those alone were $500 to have them CNC'd for the guy. He wants $2000 each. I have read that these bikes had notorious issues with piston squish, stator electronic's and other things. Is this a good deal or should I steer clear? Thank you.
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