Best Pitbike for racing

[Doc]

I thought I had started a thread on this...

I know some of you have some experience with this and I'd be happy to hear from those who THINK they know something.

For all of you that wanna chime in with ill advised stupidity...

:


I am thinking single cylinder 4 strokes. Lets even narrow it down to close to $1500 new. (No more that $2000)

Lets keep it to 10 or 12inch tires and easy to get parts and upgrades for.

Some names of makers.
Apollo
Coolster
Motovert
Pitpro
Pitster Pro
SDG
Sikk MX
SSR
Thumpstar
Workz

Pros and cons?

I found this website http://www.xtpowersports.com/Pit+Bikes.1..1.html

Are there others I should be looking at?

Thanks.

[Kurlon]

Well, first things first, WHAT kind of racing? What size tracks, motor restrictions? Lots and lots of things can sway a recommendation towards one bike or another. Personally, I like Honda XR70/CRF70s as road race mounts. Good base geometry, longer seat than a 50 derived unit, works well on both slow tight indoor tracks and fast outdoor ones, but expensive to make fast. You'll want to upgrade the rear shock, put new springs in the front, lace up a 12" front wheel... and you still haven't touched the dog ass slow stock motor.

Coolster and Appollo come from the same factory. The 'perimeter' style bikes have heavy stamped steel frames made from gray metal. Roughly KLX sized, suspension gear is the low end of the low. They like to ship crank mounted clutch based 125s, which is not going to hold up to racing, especially if you attempt hopping it up. It looks like they've made some marginal improvements in the last year, but I'd still consider them suspect. Older units sport 'Demon' forks, avoid like the plague.

Pitpro doesn't have a huge presence in the US, their primary offering is a classic 'lifted' 50 design. Short wheel base, tall frame, tall suspension, CRF50 plastic (short seat). Suspension is Genuine Marzocchi up front, non adjustable, with a midrange Fast Ace rear shock. Engines are Daytona units, Japan design, Chinese production. 12hp out of a crate 125, appear to be reliable, but are expensive and it's there aren't many mods for it yet. Bikes are over all decently produced and assembled. Short wheelbase, real tall, they'll be unstable at high speed, on tighter tracks someone riding foot out should be able to make it work. The bikes are priced out of your target range though so why'd I just waste my breath? : )

Motovert is similar to Pitpro, good quality control, decent design, and you pay for it. Most of their machines are the short wheelbase / tall frame 50 design. They do have a machine sporting 70 plastic on a longer frame that has potential for faster tracks. Suspension is fully adjustable all the way around, bike sells for $1800.

SDG - The original higher priced import pitbike, hasn't actually been on the market for 3 years now. Anything you find has been sitting for a long time and should be gone over front to back. Most of the 3v 107 Speed Minis are older units with flawed transmissions. There are also a ton of fakes on the market trying to ride SDG's name to generate some sales. In short, legit ones are going to cost more than your price range, and you don't want the ones you can afford.

Pitster Pro has a range of machines, XJR 90's are similar size to your Thumpstar 120, an entry level machine that'll work well on small tight tracks. The X2 is a short wheelbase / tall frame 50 machine. The X4 is based on aftermarket KLX110 frames, and uses 110 plastic providing for a longer seat, and a wheelbase to match it's height. No good on really tight tracks unless you ride MX style. They now have a slightly larger chassis called the LXR, one of the first big name imports on the market with a linkage based rear suspension. I'm curious to see what PK could do with it... Decent suspension, with an option to upgrade to name brand gear if you've got the cash, but not in your stated budget range.

Sikk MX hasn't really done anything for a couple years, they've got a smaller unit, again similar to your Thumpy, as well as the import standard short wheelbase tall 50 frame unit. Suspension is lower tier and would need reworking to really get the job done.

SSR has machines running the gamut from barrel scraping Coolster crap, to approaching Pitpro/Pitster Pro/Motovert quality units. Their best 'out of the crate' unit is the SSR150R, which is 70 derived, or the SSR150TX, a Pitster Pro X4 clone.

Thumpstar is similar to SSR in offering a wide range of machines, they have more consistent quality across their lineup though. The Thumpstar TDX125 Sumo is used as a spec bike in SEMRA with support from Thumpstar.

Workz is a single bike entity, and I've not seen much activity from them as of late. Their one machine is priced way out of your range, and has funky geometry. I'd pass.

Things to look out for:

- Motors:
If you're looking at a 120 or bigger, make sure it's not using a crank mounted clutch.



The round cover with two bolts on the side of the clutch cover is a dead giveaway. Also note the clutch cable goes to the front of the clutch cover, that's your other way to identify crank mounted clutches.



Note how the clutch cable goes back near the dipstick on the clutch cover, that's what you're looking for. That signifies that the machine has a primary shaft mounted clutch.

- Suspension

Avoid 'Demon' forks like the plauge. They are a 'first stab' at inverted forks by the chinese and are total junk. Parts aren't available, the seals are installed from the inside in such a way as to make them nearly impossible to replace, not that I can find any that fit anyways... They have random stiction problems as well. Total junk. Any bike sporting them is likely to be ass.



The giveaway is the two bolt mounting ridge on the front of the fork guards. If you see that, run screaming. All the other pitbike front ends use fork guards that bolt around the bottom lug without any protrusions.

Most bikes are converting to 'big bike style' flat swingarms, but aren't running linkages. They also are running their shocks near vertical, resulting in some weird shock rates as they move through their travel. They still work decently, but sometimes require a bit more effort to get dialed in. Many of the A-Arm aftermarket swingarms move the shock mount closer to the swingarm pivot to gain travel. This results in a falling rate shock situation, again a pita to tune for. The best compromise so far has been stock A-Arm setups, which maintain a decent linear rate throughout their travel. Linkage based setups are going to be cropping up all over the place soon, some are designed right, some horribly backwards, so do research before jumping into a bike with one.

[eboos]

Awesome writeup. I would also like to get a pitbike for mini roadracing in the near future.

[Doc]

Thanks Kurlon... I knew you would chime in.

Looks like Thumpstars are a good compromise.

[MotoFreak]

Best pit bike to race...at our level...?


one that runs...

[seth399]

I have been sort of looking for one and my buddies who have been racing minis/modding them for several years now basically told me to stay away from all the mini brands for the most part and just modify a klx110. They basically have 5-7grand worth of crap in their bikes though which would never be an option for me for a "fun mini bike"

[Pittenger5]

They basically have 5-7grand worth of crap in their bikes though which would never be an option for me for a "fun mini bike"

Alex was running pretty well on my bone stock KLX. Granted, he would've been far better off if it was built, but thats racing.

[seth399]

ya I think you'd need less mods to have fun on a roadcourse but offroad I think they do alot more to make it allittle roomier/better suspension along with the stupid motor/trans mods

[Kurlon]

I have been sort of looking for one and my buddies who have been racing minis/modding them for several years now basically told me to stay away from all the mini brands for the most part and just modify a klx110. They basically have 5-7grand worth of crap in their bikes though which would never be an option for me for a "fun mini bike"

There are two opinions out there, one is stick with Honda/Kawasaki/Suzuki as spending money on anything else is a toss. The other is that you can get far more bang for your buck with a lil intelligent shopping amongst the import brands.

For example, take a Pitster X4R, and toss it up against a built KLX. The base X4R is $2000, $2700 fully 'dressed' with Marzocchi Shivers up front, Elka in back.

A KLX110's MSRP is $1800. A Marzocchi Shiver front end will run you $1600. A longer travel 'big bike style' swingarm for the back is going to run you $1200 with an Elka shock. The X4R is sporting a YX160 motor, essentially a 'stroker' compared to the stock KLX110 motor, with a 4 speed and manual clutch. Add $160 for a crank, $90 for a new primary gear to eliminate the auto clutch, $50 for a shift drum to unlock 4th gear and $140 for a manual clutch kit. You'll also need a cradle kit unless you like stripping pegbar mounts on big jumps you fat bastid... $100.

Without addressing rear disc brakes (not that big a deal really) and a few other differences, that comparable KLX is going to run you over $5000. You'll never, EVER get anything close to that back if you try to turn around and sell it used. I've yet to see anyone get more than $2300 for a built to the nines used machine in the last few months. If you're comfortable doing oil changes on the forks, the import front end Pitster normally ships is a damn near perfect clone of real Shivers, including direct part compatibility. An oil change will save you another $300. The DNM shock also responds well to tuning, but it's it's own animal, so we'll say that $400 increase in the X4R's cost over base is justified.

So, dollar for dollar, the out of crate perf on the higher end imports is pretty good. The high end imports are holding up comparably to built and raced KLX110s and CRF50/CRF70s. If you're going to 'go big' they are worth considering.

Now, if you're not looking to run in the faster classes, there is something to be said for a used beater KLX. They can be had cheap, and generally hold up well. For pavement racing the stock geometry makes them ride like a choppah, slow steering and heavy feeling. On the other hand their handling lets them work a 14" front with a Michelin Pilot Sport SC where a CRF70 would struggle with the same tire thanks to less rake in the front. A CRF70 NEEDs a re-laced front wheel with a 12" rim to rock and roll. Comparing apples to apples, a stock CRF70 vs a stock KLX110 with 12s up front, the CRF70 will handle quicker but still be stable at speed compared to the lumbering KLX110 geometry. The KLX110 will have motor on the 70.

This is why knowing what you intended to do is required to make a recommendation. For someone looking to add gas and oil and putt putt around on the pavement, find a used Honda/Kawi/Suzi/Yami/etc. If you're looking to RACE against others that are serious, you have to start looking at class rules and restrictions as well as target budget. Cash is unlimited, displacement unlimited? Run an import with name brand componentry where ever you can, build two matching import motors to the nines. You can go crazy big displacement (over 200ccs at this point) producing more power than you can out of Honda 50 or KLX 110 cases but they'll be time bombs, hence maintaining a constant spare. If you're limited to a set displacement, you can usually squeeze a touch more HP out of Honda 50 / KLX 110 bottom ends per cc than import equivalents. If your cash is limited, it pays to look at the imports.

One thing to consider also if you're playing with built machines, they are no longer gas/oil/go bikes, they require more active maint schedules and they WILL break on you, regardless of country of origin. Import motors like to break cases, although there is a revised design hitting this month that should address that weak spot. KLX110s love to shatter primary shafts. Honda 50s eat 1st gears for breakfast. For the most part, the rest of the bike, frame, suspension, etc aren't a problem unless you think 120' drops off roofs of buildings sounds like fun, import or big 4 brand. Where the imports differ is the initial prep work required, while you should be retorquing and greasing/lubing everything out of the crate regardless of brand, you'll find the imports tend to have more things 'loose' than others initially. They all have their problem areas, imports it tends to be spokes wanting to loosen, but they also all have fixes, either loctite, or on the import spokes safety wiring them where they cross locks them right up nicely.

I've been racing for 4 years at this point, my big money machine I've ploughed over $18k into it, developing it, trying parts, etc. It started life as a Honda CRF70. It's currently got Japanese market suspension front and rear, including a one off hand built custom swingarm to my specs. It's got an import chinese motor in it, and is what I use to careen around Loudon when given the opportunity to. After a year of abuse I was finally able to smoke the clutch and wear out my valve springs. Up to this point the 151cc mill has been a gas/oil/go power plant with a very mild nature despite it's 16hp+ capacity.

My second '70' started life as an SDG Pro Mini. I swapped it's suspension over to a CRF70 frame as my knees couldn't deal with the 50 derived geometry, putting the seat about 2 inches above the pegs. The motor is the Honda power plant I ripped out of my main bike in search of more powah. 110cc stroker, 10hp. As long as I don't push it any further, it's a gas/oil/go motor. Anything more, and it'll be a maint nightmare. After 3 years of abuse as both a pavement and dirt mount, the import componentry hasn't so much as flinched. Parts are readily available from multiple sources, many of which are direct swappable with Honda versions.

So as long as you do your research first, and know what your goals are, I wouldn't be scared off from imports, just don't expect that $399 '150 MX Monstah' that keeps winking at you in the back corner of the local Pep Boys to be 'all that'.

[jcbell1007]

Hobbs has a nice like ktm fiddy for $495.

I would love to get into the pitbike racing but given my recent purchase, its not looking good for the time being. I think if I bought one, I would need to find a new home as well. Too many bike changes has frazzled my wife a little bit this year.

[Doc]

Hobbs has a nice like ktm fiddy for $495.

I would love to get into the pitbike racing but given my recent purchase, its not looking good for the time being. I think if I bought one, I would need to find a new home as well. Too many bike changes has frazzled my wife a little bit this year.

You could always rent one. :

[seth399]

^good read Kurlon...thanks.
And you are right with the 2 thought processes, my buddy who has the done up klx also mentioned that depending on how you do those up they will be a crap shoot as well. Specifically he was talking about a guy who put some type of bigbore kit in the 110 (forget which one) but he said it is known to have issues with reving it crazy or something and the dude had a 6000 dollar klx that he blew up the first day riding it...not fun haha

[Doc]

As to Kurlon... I have a limited frame of reference but lets talk apples and oranges.

I have the Thumpstar which I like. Is it a "50 derived" frame?

I have ridden a stock crf50 and it just won't do. Too small in the seating area and seat to peg.

The Thumpstar is better but I could use a little more room. The YSR seems closer but the pegs are to low in the stock position.

I guess what I am asking is what would have more room than the Thumpstar but still be a small enough bike to pitbike race without spending a ton?

I really don't want a 2 stroke but I might pick up that KTM from Hobbs if I come up with some cash.

[Doc]

One more thing... The KLX's (and CRF100's) Seem too big. Is there something between a Thumpstar and a CRF/xr 100 or KLX 110.

[Kurlon]

^good read Kurlon...thanks.
And you are right with the 2 thought processes, my buddy who has the done up klx also mentioned that depending on how you do those up they will be a crap shoot as well. Specifically he was talking about a guy who put some type of bigbore kit in the 110 (forget which one) but he said it is known to have issues with reving it crazy or something and the dude had a 6000 dollar klx that he blew up the first day riding it...not fun haha

Nothing's worse than piling a ton of cash, blood, sweat and tears into a bike only to have it grenade on you in short order. My first iteration of the stroker 110cc Honda powerplant did that to me at Cycles 128, I had only run it for an hour or so prior breaking it in. I was amped to have a machine I built specifically to be a dark horse beat all for the 110cc class. Went out for practice, had a guy tuck in the wet in front of me, taking me out as well. Bike stalled in the crash despite my grabbing for the clutch. Got up, tried to fire it and though I trashed the clutch as it was just kicking through. Got to the pits, looked it over and saw a hole in the head... cam chain let go, punched a hole in the head, sent the intake valve into the piston, trashed the intake valve guide, bent the valve, in short it pretty much totaled my top end. I'm running a 51mm bore instead of the normal 52mm so I can stay at 110cc with a longer 54mm stroke, makes finding pistons and cylinders a PITA. Head had to be welded up, combustion chamber redone from the valve head bouncing around, what a mess. Pissed me off. I was not a pleasant person to be around that day.

I now maintain two machines so if one tanks I've got a second option. : )

[Kurlon]

I have the Thumpstar which I like. Is it a "50 derived" frame?

Yes, the giveaway is the 50 plastic. Using that limits the seat size, as well as the overall length of the frame. As a result taller 50 derived minis have very little rake in the front, and usually obscene swingarm angles to get height. They raise the bodywork up from the motor a touch, but avoid going much further than your Thumpy as it just looks goofy with that much air space between the two.

There really isn't a 'middle' ground between your machine and the midsizes. You can get taller units, but they're just goofy. If you try to increase the seat to peg distance with different pegbars, you kill your max lean angle. I'd say you need to look into a stock Honda CRF70. It's got a longer wheelbase than your Thumpy, but not by much. Lace a 12" front on, and it'll happily steer plenty quick for tight tracks. MIK is MUCH tighter than the kart track in VT you're hoping to play at, and CRF70s and KLX110s have no problem whipping around the infield, so I wouldn't be scared off.

Going to a CRF70 or KLX110 will get you increased room between the seat and pegs, but if you're really pushing, you'll end up raising the pegs for ground clearance, putting you back in the situation you're in now. What may work better for you is switching to rearsets and clipons? I've got a set of brackets that allow you to use NSR50 rearsets on a Honda 50/70/import frame. That'll get the controls up higher, but also further back so your knees can be lower. I haven't tried them yet, but I'll see if I can track down my pics of when I did a quick test fit. I think you'll find you'll want a longer frame if you're going that route though, a lowered X4 style bike, or KLX110/CRF70 again would be where I'd start from.

[Doc]

What about the CRF/XR 100? Isn't that the same size as a KLX110?

The Thumpstar has 10" wheels. The KLX/CRF70? 12's

[Kurlon]

An XR100 is a much bigger bike all around. Interestingly the wheelbase is listed as 49.5" though, so in theory, with 12" wheels laced up it'd only be a touch longer than my 'A' bike. Going with a CRF80 instead cuts a couple inches off the wheelbase, I'd still lace up 12s front and rear. The 80's got a decent close ratio 5 speed compared to the 100's goofy 1st and 5th. On both, using 12" wheels cornering clearance is going to dictate raising the pegs I think. I'd be an interesting setup to try though. Hit up SEMRA's forum for advise on those machines, I pretty much stick with 'traditional' pitbikes so my experience with the vertical motor machines is more limited.

For comparison:

Wheelbase - Bike
36in - CRF50
40in - Thumpstar BSF Pro 125 (Modern ver of your machine)
40in - Thumpstar TDX 125 Sumo
41.9in - KLX110
42in - CRF70
47in - Pitster Pro X4R
47.6in - CRF80
48in - Kurlon's 'A' bike
49.2in - CRF100

[Doc]

Good info there. So your Pitster is still for sale right?

Oh and I don't want an automatic... Although the more I think about it, I don't shift all that much on the Pitbike track.

[Kurlon]

Motard is still for sale. Because of it's height, it's either an outdoor track only machine, or good for indoors if running foot out style, just FYI. If you're up for lowering/shortening the suspension, it should be a mean lil machine indoors as well.

And I wouldn't discount autos if running smaller motor builds, I still miss my screamer 70 auto motor... pin the throttle and click up twice to engage full warp.

[Doc]

I was thinking your pitster would be an Summer Moped, winter Ice riding machine with the occasional jaunt to the track but I have too many bikes again so I need to figure out what I am going to do with a couple of them.

[Fitz]

From a noob who started racing last year at LRRS.. how many of the techniques transfer over to full size bikes? Is it worth picking up a pitster simply to get more seat time or does the geometry lend itself to a totally different riding style?

Thanks,
Fitz

[Doc]

I think it lends itself well.

Mostly the feel of the rear breaking loose and front end feel. They are alot alike to me.

I think finding those limits on the Pit Bike are alot safer than on a big bike as well.

Transitions are quicker on the little bike so you have to think quicker.

Added bonus... you get your knee down quite easily

[Kurlon]

So far I'm finding lots of things transfer back and forth. I've been taking Gino's body position comments and applying them to my mini and finding speed, and being comfy on my mini on concrete made my first time on rain tires a blast. Like Doc said, you can explore things on the mini with less risk, and then translate that to a big bike skipping the painful learning curve you'd need if you didn't have the mini.

[SVRACER01]

alex does best on bone stock equip.