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Help Jeremy- 01 rm 250 bottoming

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Posted by: brentl---------------------

I have an 01 RM 250 . I weigh 170 and race motocross only. I bottom the rear shock too often on doubles when overjumping and/or landing flat.
Stock springs stock valving.I like to charge hard and not worry about bottoming. Fresh oil ...read up on clickers...tried at track ...seem to have little effect.
I like to do work myself. What do you guys think about the "Do it your self kits"? ( Moto-Pro,C Cycle adjusters,GP racing,....yeah Race Tech too
I have read this forum for two months ...I know Jeremy can fix it but I have a yearn to learn. I am willing to pay for know how...I understand the concept from this forum that proprietary information should not be free. (I would get a MX-Tech kit if such were available)
Jeremy I look for your comments on these kits as well.
From just outside New Orleans ...Thanks


Posted by: shaggy829---------------------

brentl
c-cycle and gp kits thats news to me. if your looking to learn rt or moto pro would be good choices .they give good instructions. that's were i got my start . these kits are low velocity large port type pistons and if you follow the valving charts you will get decent results.

shaggy


Posted by: Jeff Howe---------------------

I think it's about time I had me a up-close look at the Moto Pro kits. Did you use these Shaggy? If so how did it compare to RT in end results.


Posted by: HONDA65---------------------

I would think that the Moto Pro kits should have similar results to RT since they are an "off shoot" of Gold Valves. The guy used to be a RT dealer, but then went off and made his own. Even his packaging is the same.


Posted by: shaggy829---------------------

shocknut
well motopro fell short of rt, they are just too much flow even more that rt . both lacked compliancey and bottom resistance . the rt stuff was better than stock but not the mp stuff .the bikes were being used for mx and moto pro seems to be geared more towards off road ..
shaggy


Posted by: HONDA65---------------------

Brentl,
As a followup, you shouldn't have to change your springs at your weight. If I remember right, it comes with .43 kg up front and 5.0kg in rear. these should be plenty stiff. Just get the valving setup right.

And Jeremy might sell his kits seperatly, if he feels you can install them yourself. He sold me a set a couple of years ago.


Posted by: brentl---------------------

Thanks a lot ! C Cycle has a website which seems to indicate that you can get bottoming resistance from changing the hi/lo speed adjuster. Is this possible?
GPrcaing also has a website if you want to look but to be honest all these look look like "me too" products without much cutting edge know how.


Posted by: HONDA65---------------------

Yes, you can gain some bottoming resistance with the Hi/Lo, but its very sensitive and you'll sacrifice small bump compliance. Best to change internally. After that, most tuners will turn the Hi/Lo almost all of the way soft.


Posted by: brentl---------------------

Honda 65 ....Do you think the Type2GVs are better for what I want ? Do you know anything about new GVs ? I probably have a month to consider this (broken collarbone!).I could also hold out until Jer is back and see about his parts. Your comments please...


Posted by: cp380sx---------------------

brentl, The Race Tech valves are very good. They were originators in this replacement base valve business and have lasted the test of time. For the do it yourself guy they are an excellent option. I found that they improved my KTM forks bigtime.


Posted by: shaggy829---------------------

brent
type 2 valves are small hole pistons they are the opposite of what rt preaches highflow. rt doesn't seem to understand the type of valving to be used with small port type pistons , type 2 stuff is stiff for anything but ax ,sx or freestyle .i lived in lafayette for 10 years before i moved to texas . i know the tracks that you are riding on, type 1 gold valves will work fine . by the way is kentwood going to open up for the winter,
that track rocks!!
shaggy


Posted by: brentl---------------------

Shaggy...do not know about Kentwood. Holeshot has been redone and there are a couple big jumps there that are an example of my bottoming woes. Did you do suspension workin Lafayette? I think that you may have been on my short list to see , then you moved to TX?


Posted by: shaggy829---------------------

brentl
yes my shop was in lafayette . tx. is blinging with mx and offroad activity so here i am.
shaggy


Posted by: HONDA65---------------------

There are now 3 Gold Valves available for your RM. Type 1, which has been around forever, and is a proven product. Type 2, which has much smaller ports(though still more flow than most stock pistones) which was designed for those who want more bottoming control. Personally I would probably just run the stockers if I was considering this option.

But they just came out with the Type 3 valve, which I suspect is designed for the off-roader in mind. And these are only available for the forks. It has even larger ports than the Type 1, plus it uses a 3mm wider shim (the one against the piston) than the Type 1, which will increase the leverage as well as flow. Very plush, but I'm still working on bottoming control with them. I'm getting close, but I'm having to deviate from their shim stacking configurations. They have valving charts with the kits of course, but they don't really have any recommended valving specs yet. If you bought the kit, and got on line to use their Digital Valving, the specs the computer would give you would be for a Type 1, thus it would be too soft. I'm sure they will change it soon, but thats the way it is for now.


Posted by: marcusgunby---------------------

Honda i wouldnt be worried about going away from RTs recommended valving-ive known a few people end up with the softest setting Rt has and these arnt slow light riders.


Posted by: HONDA65---------------------

Oh yea, I'm not to worried. However, I'm having to go in the opposite direction with the new valves. I'm playing with settings that aren't even on there charts. They show alot of promise. Just more testing. Oh well, I guess that means I'm just going to have to go riding again today.


Posted by: marcusgunby---------------------

Honda65 you mention the newest RT valves use a more conventional size 1st shim?im really not sure what you gain by using a new valve with a similar set up to a std piston.If i wanted really high flow on a std piston i could just put a bleed shim on the piston and get massive flow.I guess im questioning RTs thinking behind new pistons?

I just reread you post and i see they are looking for a setup to help in woods type riding-the whole problem with there approach seems to be you then need about a 1000 shims to stop the bottoming.I bet my fork weighs less with only about 15 shims in total


Posted by: HONDA65---------------------

1st) You don't need to have a 1000 shims. Right now I count 15 shims per leg on mine. But I can see your point.

2nd) I believe this started with questions on a MX setup, and he was asking about GV's in general, and it digressed into the different valves available. As it stands today, I would recommend to someone to stay with the standard Type 1 Valve, at least for MX. For now! I didn't do any more testing on them today.

As for their thinking on the new valve, I would assume that with larger ports and a 24mm shim that deflects easier, you would have a plusher ride.

And for whatever its worth, I believe these were developed with Ty Davis. He originally was taking KTM GV's, which uses the 24mm shims to begin with and was modifing them for his Yamaha's

The new Honda's (Showas) seem to be following this aproach. their port volume makes a GV look like a pin hole. And yes, they do use ALOT of shims. But they seem to be working pretty well. Hey, whats a few extra nano-ounces?


Posted by: marcusgunby---------------------

brentL IMO the gold valves main advantage is you are really paying for the shim charts and understanding.The Gold valve quality isnt a problem.IMO you get better perfomance from std pistons.

Honda the 1000 shims was just in jest.It seamed reasonable to discuss the merits/cons of Rt as brent was thinking of buying some.


Posted by: brentl---------------------

Marcusgunby...Thanks for the opinion.Browsing the threads on this forum has shown me that this is so or nearly so. It is a good way to market the info rather than selling a piece of paper ....it helps one feel as though they have purchased something.
I suppose i might try a revalve ...since I have the shock apart now....maybe some custom parts later.


Posted by: Jeff Howe---------------------

I've looked at the Moto Pro site. I'm gonna buy them kits and test them out next year. They are the only ones I have not tested with yet and I need to try them out. For what it's worth, they are committing one of the biggest marketing mistakes known in the business world though. Bad move. Shame on them.

I'll make my point this way. When you think of "high flow" suspension, who's the first that pops into mind?


Posted by: marcusgunby---------------------

Jeff do you think they are making some wild claims-i dont know if you have read about the PDS bladder they offer?they are talking about less stiction as many others do-i tested one-if anything it was a tad firmer than the floating piston due to reduced volume(33% i think jer said)i guess im a bit bored with the marketing side of these things i think im going to set up my own piston, its a new invisible type-thats right we remove the piston competley and get a 1000% increase in flow compared to a MOTO PRO set up.


Posted by: HONDA65---------------------

Marcus, jest taken, no offense. But I understand the reasoning behind it. I've been a long time proponent of GV, having stellar success with them over the years. But I'm starting to test again with standard pistons, since I have learned a few new things over the years. And so far, I'm having really good results with them as well.

Hey what ever works.

And Shocknut, are you trying to say that by MotoPro advertising they way they do, they are actually helping Race Tech? Well, I guess thats what you get for ripping off their design. Shoot, they even use the same packaging. And their PDS bladder design looks like an EXACT copy of a W.E.R., except for the engraving.

Oh well.


Posted by: shaggy829---------------------

jeff and marcus
it is all marketing just like ics springs for twin chambers and preload springs for adjusters .anything they can make money from.
what do you guys think of that dual spring set up for pds shocks. it reminds me of works performance atv shocks with that adj. travel actuated spring system . there is know way that set up has a better transition than a pds spring . but it may be a an option for a real heavy rider over 260lbs.
shaggy


Posted by: brentl---------------------

Shaggy,Jeff,Marcus ...I thought the same about the huge flow pistoms...for fun look at ccycle.com.....I mentioned it in the beginning of this thread they say some unusual things about adjusters.
I have the following stack
- comp reb
40x.2 (8) 36x.2 (6)
30x.1 28x.1
28x.1 36x.3
38x.25 34x.3
36x.25 32x.3
34x.25 30x.3
32x.25 28x.3
30x.25 26x.3
28x.25 24x.3
26x.25 22x.3
24x.25
22x.3

I have read the factor calculatoe (thichness cubed factor). If I just want more bottoming resistance for now(maybe a piston and custom valving later) the 8 shims give a factor of 64... (10)40x.2 would give 80 is this80/64 more LSC?I am guessing that it is not 1.25 more bottoming resistance.
I f I used (3) .3 shims with a factor of 27 ....27x3=81 would it behave the same as (10) 40x.2?
Am I correct if I want to control bottoming on BIG jumps and flat landings to look at LSC?
You guys have been more than helpful and this forum rocks ...I'll soon become a lifetime member.
Brentl ....aka...Maico man


Posted by: brentl---------------------

sorry for the spacing thought I typed more spaces in but the twu columns are correct:

comp reb

40x.2 (8) 36x.2 (6)
30x.1 28x.1
28x.1 36x.3
38x.25 34x.3
36x.25 32x.3
34x.25 30x.3
32x.25 28x.3
30x.25 26x.3
28x.25 24x.3
26x.25 22x.3
24x.25
22x.3


Posted by: Jeff Howe---------------------

One of the immutable laws of marketing states that it is huge mistake to try to own the connection of a industry leader. By that I mean, that forever and a day, Race Tech has "owned" the terms "high flow" in the prospects minds. Everybody knows Race Tech for that concept or idea. So it's a huge mistake for Moto Pro to try to get people to associate that with themselves when it's Race Tech that is known for that. It just don't work out. It's a segment or niche, that RT created for themselves years and years ago, and it has been their's forever. Moto Pro will fail with that. They need to find their own niche or segment to be successful marketing their products. They will never get into the prospects mind as the king of high flow.


Posted by: HONDA65---------------------

In case you didn't know, Moto Pro used to be a Race Tech Center, the largest in the US, according to their old ads. But a couple of years ago they got the idea to copy (with some changes of course) the GV's. Needless to say they are not on RT's Christmas list anymore. In fact the last time I mentioned them to someone at RT, the phrase was F*** that guy!! They obviously were not happy about them copying their design, but I assume its different enough to head off any lawsuits.

But I guess he has a good following in the Seattle area, so maybe he has his niche there.


Posted by: Jeff Howe---------------------

nothing they can do about it. There is no patent on the design, only the name is trademarked. And the design is different anyway. It don't matter though. RT is king in high flow, if thats what you want. I really don't think Thede has much to worry about there. I could be wrong but as established as RT is I highly doubt it.


Posted by: marcusgunby---------------------

Shaggy that assister spring just looks so 70s-i wouldnt dare fit one on a modern bike.


Posted by: Jeremy Wilkey---------------------

Quote:
Originally posted by HONDA65


As for their thinking on the new valve, I would assume that with larger ports and a 24mm shim that deflects easier, you would have a plusher ride.

And for whatever its worth, I believe these were developed with Ty Davis. He originally was taking KTM GV's, which uses the 24mm shims to begin with and was modifing them for his Yamaha's

The new Honda's (Showas) seem to be following this aproach. their port volume makes a GV look like a pin hole. And yes, they do use ALOT of shims. But they seem to be working pretty well. Hey, whats a few extra nano-ounces?



I allways find it intresting that no one ever really thinks about what the valve is for.. We allways argue about high flow low flow or something inbettween. We talk about area and levarage but we don't really look at how that relates to fluid flow.

A valve is a variable orfice. The more effecent that orfice is at changeing its area, based on flow requirments, the better your suspenesion works. The Large valve face is no diferent than a smaller one if the same pviot to od ratio is mantained all things being equal. (Although it does get softer without piston lands.) What it does do is create a more stable seal, greater area for flow, and criticaly a more tunable stack. Rember we want to have maximum tunablity with the fewest posible number of shims. Our general case is we have OD's in 1mm incroments and thinkness of .05 >.1mm so with smaller valve its quite easy to be somewhere off the scale even with our nearly infenient combinations of shims. With a biger piston on the basevalve we can create a tunable system where one incroment of change has less overall impact, and this mmakes the job much easier. Also and I belive this to be a very important aspect, the lag of the system can be reduced. In other words the Check valve can close more quickly with less overall defelction. Also the shims canhave less sealing area and equal stablity.

One other thing, somewhere if ot this thread RT was given credit for the invention of the aftermarket basevalve.. No way..... Simmons was the first almost years before RT.. Eric Gorr I think knowes the name of sombody in Europe long before him too... Manytime the orginators of a concept don't get the credit they deserve..

BR,
Jer



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