Boingk's SDB Enduro Pro 250cc (Aircooled)

[monsterpitbike96]

well with that price i'd buy one they look really good this one is watercooled but it looks well built

http://www.youtube.com/watch?v=4YSNjmGx730

 

[Blender]

yea mate you should read the review of the atomik blitz. i put a link up on page 1 if u wanna read it. that'll give you an insight as to the quality of these bikes its always good to know what ur buying.

 

[boingk]

9:1 compression ratio is alright for a small displacement non-competition bike mate. These things wouldn't have the head architecture to run much more than that and be reliable, anyway, is my guess. The new comp bikes run around 13:1 I believe, but need constant rebuilds and are on the front of both materials and head design technology.

The watercooled apparently busts radiators like a champ. They look very flimsy compared to a proper competition bike. I would re-engineer them, rig a brace or more likely... just go the aircooled as out of the box its got more performance, anyway.

I would not bother installing bigger valves on these bikes. If you're after performance then just get a comp bike or a 450 to start with.

[/rant]

- boingk

 

[boingk]

Now for some pictures:

Handlebar fitment is basic. They feel alright and orientate easily by loosening the bolts and twisting the bar. Do this before anything else so you can hold the bike somewhere without braking anything.

Big spacer on the non-disc side for the front wheel. Use grease liberally during assembly or you'll end up with shagged bearings in no time.

The gold bolts need to be undone to fit the brake caliper. Position it to grab the disc (don't squeeze lever after taking out plastic spacer!) then fit bolts and tighten. Easy.

Check all bolts and clamps holding carby and fuel hosing. Grease carburettor pivots and linkages.

Assemble and grease the shock linkages or, as with the front wheel, they'll be shagged in no time. Also grease the chain and sprockets.

Sidecovers are held with 3 bolts a piece - one 10mm up top which doubles as seat retainer and two 8mm down bottom. Under this one is the airbox, oil the filter before starting.

Here is the battery installed and connected. Have electrical tape handy to ensure no shorts can happen from positive terminal to frame.

That's basically the assembly covered. Go over any other bolts and Loctite them and tension firmly but do not overtighten - you may strip them. Grease anything that moves - hand levers included. Change the oil and then start her up. She will be cantankerous (wont take throttle) for a while but just let her idle (use a big fan). Eventually she will accept throttle and it is okay to take her for a quick spin.

After 10 minutes change the oil again - mine was already discoloured. I assume because of blowby from initial breaking in. I used 15W-40 for breakin and 20W-50 is in the sump now. She takes just over a litre from drained.

That's about it guys, she seems okay to ride (just a slowish lap on even ground) and power is certainly reasonable for a Chinese 250.

Any questions just ask, tomorrow I'm heading riding with a few mates.

Cheers - boingk

 

[Blender]

so how was the front forks? i know there not adjusatable, but what is the action like whilst riding?

 

[boingk]

Haven't had a good enough ride to really comment, but they do seem smooth enough initially. Rebound could be a bit more positive though, I think.

I did take the right side fork protector off, though, as they are bloody terribly designed and foul the fork action. The left one I kept on as it carries the brake line and isn't as badly deformed. I may try reshaping the right one with a heatgun.

Overall impressions are good so far, keeping in mind the price.

- boingk

 

[Blender]

9:1 compression ratio is alright for a small displacement non-competition bike mate. These things wouldn't have the head architecture to run much more than that and be reliable, anyway, is my guess. The new comp bikes run around 13:1 I believe, but need constant rebuilds and are on the front of both materials and head design technology.

The watercooled apparently busts radiators like a champ. They look very flimsy compared to a proper competition bike. I would re-engineer them, rig a brace or more likely... just go the aircooled as out of the box its got more performance, anyway.

I would not bother installing bigger valves on these bikes. If you're after performance then just get a comp bike or a 450 to start with.

[/rant]

- boingk

wow, you certainly know your stuff mate . i've heard the same thing about the radiators, but, anythings possible with a welder! but tbh im not after performance as much as i am reliability. i mean, im sure i'll look at performance options as i get the bike, etc, but it'll all happen when i get the bike....WHEN i get it, haha

 

[Blender]

Haven't had a good enough ride to really comment, but they do seem smooth enough initially. Rebound could be a bit more positive though, I think.

I did take the right side fork protector off, though, as they are bloody terribly designed and foul the fork action. The left one I kept on as it carries the brake line and isn't as badly deformed. I may try reshaping the right one with a heatgun.


Overall impressions are good so far, keeping in mind the price.

- boingk

if i were you, i would just get some yamaha gaurds, there a straight bolt on item. that way the prblems fixed and will last.

 

[boingk]

Thanks for the tip, mate. The Yam guards might be the way I end up going.

- boingk

 

[Blender]

yeah mate, i reckon they'd look good with some yamaha plastics also. but im not sure whether you'd be able to do it. the blitz has yz plastics and the same frame as ur bike, whick has crf250 plastics...hmmm, further investigation is needed..

 

[boingk]

...hmmm, further investigation is needed..

I don't mind really.

It'll be keeping the stock plastics and graphics as I would rather spend cash on upgrades like carburettor or shocks.

Perhaps I'll get creative with some permenant markers and make it a Monster instead of a Menstor...

- boingk

 

[Snaptrax]

The atomik blitz and the sdb 250 are different. I have a Pit pro 250sxr which is the same as the atomik blitz. And a mate has the sdb 250. The components such as the forks and the rear suspension are different, The sdb forks are a lot smaller and same with the rear shock. the only thing that is sort of the same is the frame although it is a lot thinner on the sdb.

 

[zwebx]

I don't mind really.

It'll be keeping the stock plastics and graphics as I would rather spend cash on upgrades like carburettor or shocks.

Perhaps I'll get creative with some permenant markers and make it a Monster instead of a Menstor...

- boingk

if that fails you can always go with the cool hip name of Mensraitor

 

[Blender]

^^what he said

 

[Blender]

The atomik blitz and the sdb 250 are different. I have a Pit pro 250sxr which is the same as the atomik blitz. And a mate has the sdb 250. The components such as the forks and the rear suspension are different, The sdb forks are a lot smaller and same with the rear shock. the only thing that is sort of the same is the frame although it is a lot thinner on the sdb.

really, they both relatively the same, the only differences being brake rotors. well cheers mate, that really helps. so being a different rear shock , does it use different linkages? if so, that'd be pretty good, as they atomik ones are pretty crap (bad tolerances) i've heard

 

[Snaptrax]

Personally i think my pit pro is much better quality then the sdb. The linkage on my bike is nearly twice as thick then the sdb and the suspension is a lot smoother.

 

[Blender]

what is the model of your pitpro?

 

[boingk]

Hey there guys, the day of riding yesterday went well.

We carved out a nice little track on some spare land a mate said we were fine to use - a straight good for up to 4th gear, tight 180 degree righthander, tight lefthander, short straight, 70 degree righthander, short straight, right turn to the main straight again.

I'm pleased to say that the SDB held up well, it pulls strongly and handles changes of direction easily. It gives good feedback when cornering fast, too. One thing its definitely not the best for is high speeds over rough ground... but then again no bike will really be 100% doing that. I was comfortable riding it over most terrain and especially around the track.

I was able to hold my own, actually, against a mate on a CRF250R! He pulled ahead on the straights but I got distance back under brakes and through corners, which was interesting as I thought his ride felt (and obviously was) superior but didn't corner as well when I was on it - didn't have the same level of feedback in my opinion. I'm sure with more experience he will thoroughly trounce me... I was pushing pretty hard just to keep up!

The SDB came with a 520 pitch chain which looked reasonably solid, but stretched a lot early on before settling down. A few adjustments had it happy, and I lubed it after each session; we did about 1.5 hours that afternoon in 10 to 15 minute sessions.

Tyres gripped well and gave good cornering, acceleration and feedback. I only washed out once and that was only because I was pushing so hard to keep up with the CRF250.

Brakes are excellent, my mate commented that his CRF felt wooden and weak by comparison. I agreed, but I think he may have either fouled rotors of need new pads. Either way the SDB has good stoppers!

Front and rear suspension are adequate but can be jarring over rough ground. I'm not sure what can be done, so I'll probably just ride the thing until it breaks and then replace the units entirely. As I said before, feedback and grip are actually quite good. Stability midcorner and during transition is excellent.

Ergonomics aren't bad at all, either, with a firm but accommodating seat, decent bars and grips that actually help you grip... although they are very hard and 'spikey' feeling if you don't wear gloves. Great for big guys (I'm 6'2"/187cm and 90kg).

The engine is the showstopper and provides good pull from idle speeds and rips through a solid midrange before fading after a reasonable topend. You play mid to top games with this motor, use its tractability and it will reward you with solid corner exits every time. One thing I found, though, was that I rarely used first gear and was mostly in second and third, with the main straight needing fourth as well. Fifth is good for a bit over 100kmh in standard form and would most likely be good for 120+ with a smaller rear sprocket, making first a more usable gear in the process. I'm not going to mess with the engine for a while as it really is a good solid performer.

The only problem with the bike during the day was a broken chain adjuster mechanism on the rear wheel - it just snapped and left me with a crooked rear wheel to struggle with back to the pits. We quickly fished a suitable looking high-tensile nut and bolt set from my mates Patrol and in 5 minutes was good to go again. The fix lasted the rest of the day without problems.

Overall, the bike is good to ride. It is not as polished in the suspension department as the real Japanese or European bikes but the ergos, brakes and engine are all quite good. For the money it represents fantastic value and I would recommend it to anyone looking for a cheap dirtbike... and who also has the necessary skills to fix problems when they arise.

I'll upload pictures and a video when I can.

Cheers - boingk

 

[boingk]

Here are some photos of the bikes:

The SDB all clean and shiny:

SDB after a day of riding:

Snapped chain adjuster:

Replacement adjuster:

Hellava day!

- boingk

 

[Blender]

sweet mate, looks like it held up well. i would contribut the bad ride quality over rough ground to the linkages, there pretty bad (so i've heard), i think im turned to the aircooled one !